168 miRNA LEVELS DURING BOVINE PREIMPLANTATION EMBRYONIC DEVELOPMENT

2008 ◽  
Vol 20 (1) ◽  
pp. 164
Author(s):  
D. K. Berg ◽  
S. E. Beaumont ◽  
P. L. Pfeffer
Keyword(s):  
Cellular Proliferation ◽  
Expression Profiles ◽  
Polar Body ◽  
Gene Expression Profiles ◽  
Donor Cell ◽  
Vitro Fertilization ◽  
Mrna Targets ◽  
Copy Numbers ◽  
First Polar Body

MicroRNAs (miRNAs) are a class of naturally occurring non-coding RNAs that play a role in gene regulation. They are highly conserved, single-stranded RNAs, 22 nucleotides in length, that are cleaved from larger inactive hairpin precursor transcripts, and use the RNA interference-related pathways to repress their mRNA targets. They play diverse regulatory roles in cellular proliferation, morphogenesis, apoptosis, and differentiation. Maternal miRNAs are crucial for early mammalian development (Murchison et al. 2007 Genes Dev. 21, 682–693; Tang et al. 2007 Genes Dev. 21, 655–648), while sperm-borne miRNAs do not contribute significantly to miRNAs in the zygote (Amanai et al. 2006 Biol. Reprod. 75, 877–884). Our objective was to identify miRNAs that are expressed during bovine in vitro oocyte maturation (MII) and blastocyst stages as well as during parthenogenic development. MII oocytes (n = 1680) were generated from abattoir-derived oocytes and matured in vitro for 24 h. Cumulus cells were removed and the first polar body was visually assessed before the oocytes were frozen in liquid N2. Parthenogenic blastocysts (n = 575) were produced using ionomycin/6DMAP activation, and IVF blastocysts (n = 1150) were produced using standard in vitro fertilization followed by in vitro culture in synthetic oviduct fluid (Thompson et al. 2000 J. Reprod. Fertil. 118, 47–55). Blastocysts (grades 1 and 2) were selected on Day 7 post-activation/insemination and frozen in liquid N2. RNA was isolated using the mirVana miRNA isolation kit (Ambion, Scoresby, Victoria, Australia). miRNAs were quantified using the TaqMan� MicroRNA Human Panel-Early Access Kit (Applied Biosystems, Scoresby, Victoria, Australia) following the manufacturer's protocol. Absolute copy numbers per embryo were estimated. Of the 157 miRNAs in the panel, 102, 136, and 118 were detected above background in oocytes, IVF, and parthenogenic blastocysts, respectively. Only 28 miRNAs were present at over 100 copies in MII oocytes, with maximum levels reaching 1300 copies. Levels were generally much higher at blastocyst stages, with 21 miRNAs present at more than 10 000 copies. miR-16 was one of the most abundant miRNAs in all samples tested. Copy numbers per blastomere cell were 5-fold higher in IVF blastocysts compared to parthegenotic blastocysts for miR-19a, 21, and 30b. The low copy numbers of mature miRNAs before embryonic genome activation may have implications for somatic cell nuclear transfer experiments in that exogenously added miRNAs from the donor cell could impact on the embryonic gene expression profiles.

74 IN VIVO SURVIVAL OF DOMESTIC CAT OOCYTES AFTER VITRIFICATION, INTRACYTOPLASMIC SPERM INJECTION, AND TRANSFER TO RECIPIENTS

2008 ◽  
Vol 20 (1) ◽  
pp. 118 ◽  
Author(s):  
M. C. Gómez ◽  
N. Kagawa ◽  
C. E. Pope ◽  
M. Kuwayama ◽  
S. P. Leibo ◽  
...  
Keyword(s):  
Intracytoplasmic Sperm Injection ◽  
Polar Body ◽  
Oocyte Retrieval ◽  
Cumulus Cells ◽  
Domestic Cat ◽  
Minimal Amount ◽  
Vitro Fertilization ◽  
First Polar Body

The ability to cryopreserve female gametes efficiently holds immense economic and genetic implications. The purpose of the present project was to determine if domestic cat oocytes could be cryopreserved successfully by use of the Cryotop method. We evaluated (a) cleavage frequency after in vitro fertilization (IVF) v. intracytoplasmic sperm injection (ICSI) of in vivo- and in vitro-matured oocytes after vitrification, and (b) fetal development after transfer of resultant embryos into recipients. In vivo-matured cumulus–oocyte complexes (COCs) were recovered from gonadotropin-treated donors at 24 h after LH treatment, denuded of cumulus cells, and examined for the presence of the first polar body (PB). In vitro-matured COCs were obtained from ovaries donated by local clinics and placed into maturation medium for 24 h before cumulus cells were removed and PB status was determined. Oocytes were cryopreserved by the Cryotop method (Kuwayama et al. 2005 Reprod. Biomed. Online 11, 608–614) in a vitrification solution consisting of 15% DMSO, 15% ethylene glycol, and 18% sucrose. For IVF, oocytes were co-incubated with 1 � 106 motile spermatozoa mL–1 in droplets of modified Tyrode's medium in 5% CO2/air at 38�C (Pope et al. 2006 Theriogenology 66, 59–71). For ICSI, an immobilized spermatozoon was loaded into the injection pipette, which was then pushed through the zona pellucida into the ooplasm. After a minimal amount of ooplasm was aspirated into the pipette, the spermatozoon was carefully expelled, along with the aspirated ooplasm. After ICSI, or at 5 or 18 h post-insemination, in vivo- and in vitro-matured oocytes, respectively, were rinsed and placed in IVC-1 medium (Pope et al. 2006). As assessed by normal morphological appearance after liquefaction, the survival rate of both in vivo- and in vitro-matured oocytes was >90% (93–97%). For in vitro-matured oocytes, cleavage frequencies after IVF of control and vitrified oocytes were 73% (16/22) and 53% (30/57), respectively, as compared to 68% (19/28) after ICSI of vitrified oocytes (P > 0.05). For in vivo-matured oocytes, cleavage frequencies after IVF of control and vitrified oocytes were 55% (18/33) and 35% (6/17), respectively, compared to 50% (10/20) after ICSI of vitrified oocytes (P > 0.05). At 18–20 h after ICSI, 18 presumptive zygotes and four 2-cell embryos derived from vitrified in vitro-matured oocytes and 19 presumptive zygotes produced from seven in vivo-matured and 12 in vitro-matured vitrified oocytes were transferred by laparoscopy into the oviducts of two recipients at 24–26 h after oocyte retrieval. The two recipients were 9-month-old IVF/ET-derived females produced with X-sperm sorted by flow cytometry. At ultrasonography on Day 22, both recipients were pregnant, with three live fetuses observed in one recipient and one live fetus seen in the second recipient. On Day 63 and Day 66 of gestation, four live kittens were born, without assistance, to the two recipients. The one male and three female kittens weighed an average of 131 g. In summary, in vivo viability of zygotes/embryos produced by ICSI of cat oocytes vitrified by the Cryotop method was demonstrated by the birth of live kittens following transfer to recipients.

scholarly journals In vitro Fertilization in Iraqi Local Goats

2009 ◽  
Vol 3 (1) ◽  
pp. 5-9
Author(s):  
Hazim I. AL-Ahmed
Keyword(s):  
Tissue Culture ◽  
In Vitro Fertilization ◽  
Culture Medium ◽  
Polar Body ◽  
Culture Technique ◽  
Tissue Culture Medium ◽  
Vitro Fertilization ◽  
Cumulus Oophorus ◽  
First Polar Body

412 primary ova were used in the study of in vitro fertilization, these ova were collected from ovaries samples of does at different stages of oestrous cycle collected from abattoirs.These follicles were classified according to their size into large follicles (> 2-6 mm) and small follicles (1-2 mm). Ova aspirated from these follicles were evaluated depending on the presence or absence of cumulus oophorus cells and on the presence of the first polar body. The aspirated ova from large and small follicles were maturated in tissue culture medium 199 to study their ability of maturation.. The microdrops technique from tissue culture (Medium 199) and granulosa cell co-culture technique were used for the maturation of ova, also the in vitro fertilization was inducted in these ova with the sperm which were capacitated in Bracket Medium. The results showed that the highest rate for ova aspiration and the highest rate of ova surrounded by cumulas oophorus were from the large, follicles. The size of follicle has a significant influence on the degree of ova growth and maturation. The results showed the absence of significant differences in the efficacy of two techniques used in the ova maturation and their ability of fertilization.

81 THE EFFECT OF FOLLICULAR AND OVIDUCT OOCYTES ON THE DEVELOPMENT OF RABBIT NUCLEAR TRANSFERRED EMBRYOS IN VITRO

2010 ◽  
Vol 22 (1) ◽  
pp. 199
Author(s):  
L.-Y. Sung ◽  
C.-H. Chen ◽  
T.-A. Lin ◽  
L.-J. Sung ◽  
H.-Y. Su ◽  
...  
Keyword(s):  
Polar Body ◽  
Fluorescent Microscopy ◽  
Donor Cell ◽  
Cumulus Cells ◽  
Fusion Rate ◽  
Adult Rabbit ◽  
Cleavage Rate ◽  
Developmental Potential ◽  
First Polar Body

This study was designed to examine the effect of rabbit oocytes collected from oviducts v. follicles on the developmental potential of nuclear transplant (NT) embryos. Rabbit oocytes were flushed from the oviducts (oviduct oocytes) or collected from the ovarian Graafian follicles(follicular oocytes) of superovulated does at 12 h post-hCG injection (hpi). Cumulus cells were then removed from the oocytes by incubation in 0.5% hyaluronidase and pipetting. Oocyte enucleation was conducted in TCM-199 +10% fetal bovine serum (FBS) and confirmed under fluorescent microscopy. Skin fibroblasts from an adult rabbit were prepared and cultured to passage 8 to 10 before use as nuclear donors. A donor cell with a diameter of approximately 15 to 19 μm was transferred into the perivitelline space of an enucleated oocyte and subsequently fused with the recipient oocyte by applying 3 direct current pulses at 3.2 kV cm-1 for 20 μs per pulse. Fused oocytes were activated by the same electrical stimulation described above, and then cultured in TCM-199 + 10% FBS containing 2.0 mM 6-DMAP and 5 μg mL-1 cycloheximide for 1 h. Cloned embryos were cultured in 2.5% FBS B2 medium in 5% CO2 and 95% humidified air at 38.5°C for 3 d. Embryo development to cleavage (2- to 4-cell), 8-cell, and morula/blastocyst (Mor/BL) stages was evaluated. The data were analyzed by the General Linear Model procedure (SPSS 11.0, SPSS Inc., Chicago, IL, USA).The total number of oocytes collected per animal was 27.6 ± 1.3, with 47.8% from oviducts, and 52.2% from follicles. The percentage of oviduct oocytes that showed the first polar body was 98.3% (n = 150) at the time of collection, whereas follicular oocytes only had 54.8% at collection (n = 93), but it reached 92.4% when immature follicular oocytes were cultured for 3 h in vitro. The enucleation rates were similar between the follicular (82.7%) and the oviduct (79.1%) groups. Table 1 shows that a significantly higher fusion rate was found in follicular oocytes compared with that in the oviduct group (90.8 v. 63.4%; P < 0.05). There was no difference in the cleavage rate and Mor/BL development between the 2 groups, although the 8-cell(78.4 v. 63.9%; P = 0.11) and the overall efficiencies (30.6% v. 17.9%; P = 0.14) appeared higher in the follicular group. These results demonstrated that rabbit follicular oocytes at 12 hpi have potential equivalent or maybe better (fusion) than that with oviduct oocytes for promoting the preimplantational development of NT embryos. Table 1.The effect of follicular and oviduct oocytes on the development of rabbit NT embryos Supported by NIH1R43 RR023774-01A1 and 5R44HL091605-03.

32 EFFECTS OF FUSION/ACTIVATION METHODS ON DEVELOPMENT OF EMBRYOS PRODUCED BY NUCLEAR TRANSFER OF PORCINE FETAL FIBROBLASTS

2007 ◽  
Vol 19 (1) ◽  
pp. 134
Author(s):  
P. Q. Cong ◽  
E. S. Song ◽  
E. S. Kim ◽  
Z. H. Li ◽  
Y. J. Yi ◽  
...  
Keyword(s):  
Nuclear Transfer ◽  
Polar Body ◽  
Metaphase Plate ◽  
Donor Cell ◽  
Blastocyst Stage ◽  
Pulse Number ◽  
Donor Cells ◽  
First Polar Body ◽  
Fetal Fibroblasts

Pigs have become increasingly important in the field of biomedical research, and interest has grown in the use of transgenic cloned pigs as potential xenograft donors. The present study were carried out to investigate the effects of intensity of DC pulse, number of DC pulses, and equilibration before fusion/activation on developmental ability of porcine embryos derived from nuclear transfer. Porcine cumulus-oocyte complexes (COCs) were cultured in modified TCM-199 (mTCM-199) medium for 44 h at 38.5�C, 5% CO2 in air. After in vitro maturation (IVM), metaphase II oocytes were selected for enucleation. Porcine fetal fibroblasts were obtained from a porcine fetus on Day 35 of gestation as donor cells. Oocytes were enucleated by removing, with a micropipette, the first polar body along with adjacent cytoplasm containing the metaphase plate; then a donor cell was injected in contact with the cytoplasm of each oocyte. In experiment 1, several different fusion/activation intensities (two DC pulses of 0.4, 0.8, 1.2, 1.6, and 2.0 kV cm-1 for 30 �s) were carried out to investigate the effect on the development of nuclear transfer embryos. In experiment 2, the reconstructed oocytes were fused and activated with 1, 2, or 3 DC pulses of 1.2 kV cm-1 for 30 �s. In experiment 3, reconstructed oocytes were equilibrated in mTCM-199 medium at 38.5�C, 5% CO2 for 0, 1, 2, 3, 4, 5, and 6 h. After equilibration, the reconstructed oocytes were fused and activated with one DC pulse of 1.2 kV cm-1 for 30 �s in fusion medium. The reconstructed embryos were transferred into PZM-3 medium containing 0.3% BSA for further culture. The rates of embryo cleavage and development of blastocyst stage were evaluated at 48 h and 6-7 days, respectively. The cell numbers of blastocysts were counted by using Hoechst 33342 epifluorescence staining. Data were analyzed by ANOVA and Duncan

186 SUPPLEMENTATION WITH LOW DOSES OF DIMETHYL SULFOXIDE DURING IN VITRO MATURATION RESULTS IN IMPROVED IN VITRO EMBRYO PRODUCTION IN CATTLE

2017 ◽  
Vol 29 (1) ◽  
pp. 201
Author(s):  
A. E. Ynsaurralde ◽  
M. Suvá ◽  
R. Bevacqua ◽  
S. Munilla ◽  
C. Luchetti ◽  
...  
Keyword(s):  
Dimethyl Sulfoxide ◽  
Embryo Development ◽  
In Vitro Maturation ◽  
Polar Body ◽  
Predictive Equation ◽  
Embryo Production ◽  
Vitro Fertilization ◽  
First Polar Body ◽  
In Vitro Embryo Production

Oocyte in vitro maturation (IVM) is crucial for subsequent in vitro embryo production. It involves acquisition of competence for fertilization and embryo development. Therefore, its optimization could have a direct impact on in vitro embryo development. Dimethyl sulfoxide (DMSO) is commonly used as solvent or vehicle, but also increases the membrane permeability and behaves as a scavenger of cytotoxic free radicals. The aim of this study was to evaluate the effect of DMSO supplementation during bovine oocyte maturation on subsequent in vitro embryo development and to determine the optimal usage dose with no toxic effect. To this aim, cumulus-oocyte complexes were collected from slaughterhouse ovaries and IVM in TCM 199 containing 10% fetal bovine serum, 10 µg mL−1 of FSH, 0.3 mM sodium pyruvate, 100 mM cysteamine, and 2% antibiotic-antimycotic. The oocytes were incubated for 24 h at 6.5% CO2 in humidified air at 38.5°C. For Experiment 1, IVM medium was supplemented with DMSO at concentrations of 0, 0.1, 0.5, 1, or 10% (vol/vol) DMSO (n = 241, 195, 42, 192, 172 oocytes) and IVM rate was determined by presence of the first polar body. For Experiment 2, 0, 0.1, 0.25, 0.5, 0.75, 1, or 10% (vol/vol) DMSO (n = 446, 322, 65, 194, 77, 250, 39 oocytes) was supplemented to IVM medium and cleavage and blastocyst rates were determined to establish the optimal usage dose. In vitro fertilization was performed according to Brackett and Oliphant (1975), with 16 × 106 spermatozoa/mL for 5 h. Afterwards, presumptive zygotes were cultured in SOF for 7 days at 38.5°C and 5% O2. Cleavage and blastocyst rates were determined on Days 2 and 7, respectively. Results were statistically analysed using Fisher’s exact test by GraphPad Prism software (GraphPad Software Inc., La Jolla, CA, USA). Also, the percentage of blastocyst was adjusted to DMSO concentration using the R software quadratic regression model. The optimum usage dose was determined by calculating the maximum of the estimated predictive equation. In vitro maturation in 10% DMSO resulted in significantly lower first polar body extrusion rates (0% = 74%a, 0.1% = 73%a, 0.5% = 83%a, 1% = 66%a, and 10% = 8%b; different letters indicate statistical differences) and lower cleavage rates (0% = 75%a, 0.1% = 77%a, 0.25% = 80%a, 0.5% = 79%a, 0.75% = 78%a, 1% = 77%a, and 10% = 3%b) than the other treatments. Furthermore, blastocyst production was higher for the 0.25 and 0.5% (vol/vol) supplemented DMSO groups (0% = 26%b, 0.1% = 37%ab, 0.25% = 40%a, 0.5% = 41%a, 0.75% = 34%ab, 1% = 23%b, and 10% = 0%c). The predictive equation results indicate that the maximum percentage of blastocysts is obtained with a concentration of 0.458% (vol/vol) of DMSO. In conclusion, DMSO supplementation during IVM of bovine oocytes had a positive effect on in vitro development. Further studies will be carried out to elucidate its mechanism of action.

scholarly journals Oocyte Selection for In Vitro Embryo Production in Bovine Species: Noninvasive Approaches for New Challenges of Oocyte Competence

Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2196
Author(s):  
Luis Aguila ◽  
Favian Treulen ◽  
Jacinthe Therrien ◽  
Ricardo Felmer ◽  
Martha Valdivia ◽  
...  
Keyword(s):  
Polar Body ◽  
Developmental Competence ◽  
Oocyte Diameter ◽  
Vitro Fertilization ◽  
Oocyte Competence ◽  
Livestock Species ◽  
Large Oocyte ◽  
First Polar Body ◽  
Major Interest

The efficiency of producing embryos using in vitro technologies in livestock species rarely exceeds the 30–40% threshold, indicating that the proportion of oocytes that fail to develop after in vitro fertilization and culture is considerably large. Considering that the intrinsic quality of the oocyte is one of the main factors affecting blastocyst yield, the precise identification of noninvasive cellular or molecular markers that predict oocyte competence is of major interest to research and practical applications. The aim of this review was to explore the current literature on different noninvasive markers associated with oocyte quality in the bovine model. Apart from some controversial findings, the presence of cycle-related structures in ovaries, a follicle size between 6 and 10 mm, large number of surrounding cumulus cells, slightly expanded investment without dark areas, large oocyte diameter (>120 microns), dark cytoplasm, and the presence of a round and smooth first polar body have been associated with better competence. In addition, the combination of oocyte and zygote selection via brilliant cresyl blue (BCB) test, spindle imaging, and the anti-Stokes Raman scattering microscopy together with studies decoding molecular cues in oocyte maturation have the potential to further optimize the identification of oocytes with better developmental competence for in-vitro-derived technologies in livestock species.

In vitro fertilization and cleavage of mouse oocytes recombined with the first polar body

2008 ◽  
Vol 5 (2) ◽  
pp. 169-173 ◽  
Author(s):  
Wang Gong-Jin ◽  
Tan Xiao-Dong ◽  
Zhou Xiao-Long ◽  
Xu Xiao-Bo ◽  
Fan Bi-Qin
Keyword(s):  
Polar Body ◽  
Farm Animals ◽  
Blue Staining ◽  
Vitro Fertilization ◽  
Mouse Oocytes ◽  
Polar Bodies ◽  
First Polar Body ◽  
Different Temperatures ◽  
Further Development

AbstractThe developmental functions of oocytes of three strains of mice (Kunming, ICR and C57BL/6-Tg(CAG-EGFP)C14-Y01-FM131Osb) recombined with the nuclei of first polar bodies (Pbs I) were explored. Cumulus oocyte complexes (COCs) from the mice were collected after superovulation, then Pbs I were obtained from the COCs by 2% pronase treatment. The survival of Pbs I under different temperatures was identified by morphology and trypan blue staining. Later, the polar body I (Pb 1) nucleus and a little cytoplasm was injected into each oocyte, the nuclei of which had been enucleated by micromanipulation. Oocytes recombined with Pbs I were fertilized, then cultured in vitro in order to observe their further development. The results showed that the vigour of Pbs I was maintained for 12–14 h after superovulation, and was still maintained after 48 h at 4 °C. A total of 13 out of 117 recombined oocytes from Kunming and ICR mice, as well as 3 out of 38 recombined oocytes from C57BL/6-Tg(CAG-EGFP)C14-Y01-FM131Osb mice, developed into two-cell embryos. The experiments confirmed that mouse oocytes recombined with the nuclei of Pbs I could maintain fertilization and development. These results present valuable references for further utilization of genetic resources for farm animals

156 EFFECTS OF MORPHOLOGY TYPE OF POLAR BODY ON PORCINE OOCYTE QUALITY AND DEVELOPMENTAL POTENTIAL AFTER IN VITRO FERTILIZATION

2014 ◽  
Vol 26 (1) ◽  
pp. 192
Author(s):  
L. Cai ◽  
E. Kim ◽  
S. U. Hwang ◽  
J. D. Yoon ◽  
Y. Jeon ◽  
...  
Keyword(s):  
Polar Body ◽  
Oocyte Quality ◽  
Developmental Competence ◽  
Penicillin G ◽  
Cleavage Rate ◽  
Developmental Potential ◽  
Vitro Fertilization ◽  
First Polar Body

Evaluation of morphology of first polar body (1st PB) could be a method for the oocyte's quality and developmental competence. The developmental potential of oocyte with fragmented PB after in vitro maturation (IVM) is a controversial issue. The aim of this study is to investigate the effects of PB morphology type on oocyte quality and developmental competence after IVF. Porcine ovaries were obtained from prepubertal gilts at a local slaughterhouse and transported to the laboratory within 2 h in physiological saline supplemented with 100 IU mL–1 penicillin G and 100 mg mL–1 streptomycin sulfate. The cumulus–oocyte complexes (COC) were aspirated using an 18-gauge needle attached to a 10-mL disposable syringe from superficial follicles 3 to 6 mm in diameter followed by IVM. After IVM, oocytes were classified into 3 types as follows, oocytes with normal PB (A type), oocytes with a little of fragmented PB (B type), and oocytes with separated 2 PBs (C type), respectively. As classification of PB types, we analysed the distribution ratio of each PB type after IVM, and then performed IVF for analysis of fertilization rate and developmental potential. The ratio of oocyte with A type (73%) was significantly (P < 0.05) higher than that of B type (24.5%) or C type (2.5%) after IVM. Only mature oocytes were selected from A and B type and were subjected to IVF because of a small number of oocytes with C type. In the IVF experiment, the efficiency of monospermy and fertilization were significantly higher in oocytes of A type (46.7%) than those of type B (20.0%). The cleavage rate of oocytes with A type (63.9%) was significantly (P < 0.05) higher than the oocytes with B type (43.8%). Embryonic developmental competence to the blastocyst stage after IVF was significantly (P < 0.05) higher in the A-type oocytes (26.3%) than in the B-type oocytes (16.9%). The levels of glutathione and reactive oxygen species were not affected by the morphological classification of the PB. In summary, these results suggest that polar body morphology could be a marker of oocyte quality after IVM. We are currently studying gene expression of each oocytes and blastocysts. This work was supported, in part, by a grant from the Next-Generation BioGreen 21 Program (No. PJ00956901), Rural Development Administration, and the National Research Foundation of Korea Grant funded by the Korean Government (NRF-2012R1A1A4A01004885, NRF-2013R1A2A2A04008751), Republic of Korea.

102 EFFECT OF DEMECOLCINE PRE-TREATMENT ON VIABILITY, TIMING OF FIRST POLAR BODY EXTRUSION, SPINDLE CONFIGURATION, AND SUBSEQUENT DEVELOPMENT OF OVINE OOCYTES VITRIFIED AT GERMINAL VESICLE STAGE

2010 ◽  
Vol 22 (1) ◽  
pp. 210 ◽  
Author(s):  
A. R. Moawad ◽  
J. Zhu ◽  
I. Choi ◽  
K. H. S. Campbell
Keyword(s):  
Polar Body ◽  
Germinal Vesicle ◽  
Subsequent Development ◽  
Developmental Competence ◽  
Blastocyst Development ◽  
Vitro Fertilization ◽  
First Polar Body ◽  
Polar Body Extrusion ◽  
And Control

Oocyte cryopreservation is a potentially valuable way of preserving female germ cells. However, to date the reported developmental competence of cryopreserved oocytes is low. The objectives of this study were to investigate the effects of demecolcine pretreatment on viability, timing of the first polar body extrusion (PBI), spindle, chromatin organization, and in vitro embryo development of ovine vitrified germinal vesicle (GV) oocytes after in vitro fertilization (IVF) and parthenogenetic activation. Cumulus-oocyte complexes (COC) aspirated from ovine ovaries collected at slaughter were selected and randomly divided into 3 groups: (1) untreated (in vitro matured, IVM) as a control, (2) vitrified (Moawad AR et al. 2009 Reprod. Fertil. Dev. 21, 135 abst), and (3) deme + vitrified (oocytes were incubated with 0.1 μg mL-1 demecolcine for 20 min before vitrification). After vitrification COC were thawed and matured in vitro for 24 h. Following IVM, oocytes from 3 groups were subsequently subjected to (1) immunostaining, (2) IVF, or (3) activation. Presumptive zygotes were cultured in vitro in SOF media for 7 days. Data were analyzed using chisquare and t-test. No significant differences (P > 0.05) were observed in survival rates between deme + vitrified (90.8%, 324/357) and vitrified (87.2%, 211/242). However, the numbers of oocytes with PBI in two vitrified groups at 18 h (20.4 and 8.5 v. 47.1%) and 24 h post IVM (51 and 43.2 v. 88.5%) were significantly lower (P < 0.01) than those in the control. Percentage of normal spindle and chromatin configuration in the two vitrified groups also significantly decreased (P < 0.05) compared with those in the control (42.5 and 41.8 v. 76.5%), whereas missing spindle in the 2 vitrified groups significantly increased (P < 0.001) compared with the controls (47.5 and 32.7 v. 3.9%). Following IVF (pi), cleavage rates at 24.48 hpi and morula development (5 days pi) were significantly lower (P < 0.001) in deme + vitrified (6.1, 43.1, and 28.5%) and vitrified groups (3.3, 30.1, and 22.9%) than control (50.4, 82.4, and 46.4%). Blastocyst development in deme + vitrified (9.8%) and control (33.6%) was significantly higher (P < 0.01) than in vitrified group (1.3%). Hatched blastocysts were observed only in deme + vitrified and control groups (4.9 v. 12.8%). In addition, post activation (pa) cleavage rates in deme + vitrified (10.3 v. 40.7%) and control (52.5 v. 76.7%) at 24 and 48 hpa were significantly higher (P < 0.05) than those in the vitrified group. Blastocyst development in deme + vitrified (4.8%) was higher than that in the vitrified group (1.8%), but not significant (P > 0.05); however, these values were still significantly lower (P < 0.001) than those in the control (24.2%). No significant differences were observed in total cell numbers per blastocyst between all the groups. Taken together, these results suggest that pretreatment of oocytes with demecolcine before vitrification could improve the developmental competence of ovine vitrified-thawed GV-stage oocytes. A. R. Moawad was supported by the Egyptian government.

165 Effect of Dimethyl Sulfoxide Supplementation During In Vitro Maturation on the Genetic Expression Pattern of Bovine Blastocyst

2018 ◽  
Vol 30 (1) ◽  
pp. 222
Author(s):  
A. E. Ynsaurralde-Rivolta ◽  
M. Suvá ◽  
R. Bevacqua ◽  
L. Rodriguez-Alvarez ◽  
A. Velasquez ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Fragmentation ◽  
Expression Pattern ◽  
In Vitro Maturation ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Stem Cell Differentiation ◽  
Marker Genes ◽  
Vitro Fertilization

Supplementation of bovine oocytes with 0.5% (v/v) dimethylsulfoxide (DMSO) during in vitro maturation (IVM) results in increased blastocysts rates (Ynsaurralde et al. 2016 Reprod. Fertil. Dev. 29, 201-202). Recently, an important role of DMSO in stem cell differentiation has been observed, attributed to modulation of gene expression. However, the effect of DMSO suplementation during in vitro maturation on gene expression profiles and embryo quality have not been evaluated so far. Thus, we examinated the effect of DMSO during IVM on the expression of some key genes (Sox2, Oct4, and Cdx2) and on the degree of DNA fragmentation at the blastocyst stage. To this aim, cumulus–oocyte complexes collected from slaughterhouse ovaries were matured in TCM-199 containing 10% fetal bovine serum, 10 µg mL−1 FSH, 0.3 mM sodium pyruvate, 100 mM cysteamine, and 2% antibiotic-antimycotic for 24 h, at 6.5% CO2 in humidified air and 38.5°C. Maturation media was supplemented with 0, 0.5, or 0.75% (v/v) DMSO. In vitro fertilization (IVF) was performed with 16 × 106 spermatozoa per mL for 5 h. Afterwards, presumptive zygotes were cultured in SOF for 7 days at 38.5°C and 5% O2. Three pools of 5 blastocysts were analysed for each treatment. Gene expression analysis was performed by real-time qPCR and DNA fragmentation of blastocysts was measured by TUNEL assay (n = 8, 7, and 14 blastocysts analysed for 0, 0.5, and 0.75% v/v DMSO, respectively). The results were statistically analysed using ANOVA with a completely randomised model by InfoStat software Version 1.1 (https://www.infostat.com.ar/). The pluripotency marker genes Sox2 and Oct4 were up-regulated in blastocysts only when the oocytes were matured in 0.75% DMSO, whereas the trophoblastic marker Cdx2 showed no differences among treatments. No differences were detected in the number of TUNEL-positive cells among treatments: 10/65 (15%) in 0%, 19/110 (18%) in 0.5%, and 18/98 (20%) in 0.75% (v/v) DMSO. In conclusion, supplementation with 0.5% (v/v) DMSO, as previously published, increases the production of blastocysts without disrupting the expression pattern of the evaluated genes.

Sign in / Sign up

Export Citation Format

Share Document