84 PORCINE EMBRYOS UTILIZE SMALL AMOUNTS OF PYRUVATE, LACTATE, AND GLUCOSE IN VITRO

2016 ◽  
Vol 28 (2) ◽  
pp. 171
Author(s):  
B. R. Redel ◽  
L. D. Spate ◽  
B. Elliott ◽  
M. Paczkowski ◽  
R. L. Krisher ◽  
...  
Keyword(s):  
Gene Expression ◽  
Embryo Culture ◽  
Glucose Transporters ◽  
Cell Number ◽  
Blastocyst Stage ◽  
Early Embryo ◽  
Energy Substrates ◽  
Stage Embryo

Porcine embryo culture systems are suboptimal to the in vivo environment, and significant effort has been made to improve development to the blastocyst stage in vitro. Since metabolism of the early embryo has many similarities to the Warburg effect, our goal was to determine the role of glucose on development, gene expression, and metabolism of other energy substrates in the blastocyst stage embryo. Pig embryos were in vitro produced and cultured in MU1 containing pyruvate, lactate, amino acids, and either 0, 7.5, 15, or 250 µM glucose, N = 1164, 4 replications. There was no difference in blastocyst percentage between the 0 µM and 7.5 µM glucose (34% ± 6.5 v. 29% ± 8.2), but there was a decrease in development in response to 15 and 250 µM compared with 0 µM glucose (25% ± 8.5, 23% ± 8.7 v. 34% ± 6.5; P ≤ 0.01). Glucose transporters (SLC2A1 and SLC2A2) and hexokinases (HK1 and HK2) were analysed by qPCR to detect differences in gene expression, 3 replicates containing 10 blastocyst pools. The abundance of both HK1 and HK2 was decreased in blastocysts cultured with 7.5 µM glucose compared with 0 µM (P ≤ 0.04). Glucose transporters were not affected by glucose supplementation (P ≥ 0.5). Metabolic data were collected to determine if embryos were adjusting their energy substrate use in response to glucose. Two assays were completed to determine lactate and pyruvate consumption or release into the media by embryos, in comparison with media without embryos. In vitro-produced embryos were cultured in MU1 with 0 or 7.5 µM glucose N = 360, 4 replications. Both treatments consumed lactate, but there were no differences between treatments (6.8 ± 9.4 pmol/blastocyst/h v. 12.5 ± 1.6 pmol/blastocyst/h; P = 0.6). Blastocysts cultured in 7.5 µM glucose consumed pyruvate, whereas blastocysts without glucose produced pyruvate (–0.34 ± 0.3 pmol/blastocyst/h v. 0.73 ± 0.2 pmol/blastocyst/h; P < 0.01). It has been suggested that fructose is a more efficient replacement for glucose in pig embryo culture. Therefore, we produced pig embryos in vitro and cultured these embryos in MU1, MU1 + 2 mM glucose, or MU1 + 2 mM fructose to the blastocyst stage, 4 replications, N = 389. Again, there was a decrease in embryos that developed to the blastocyst stage in 2 mM glucose compared with MU1 control blastocysts (26% ± 5.8 v. 11% ± 2.5; P = 0.001), but there was only a trend for a decrease in development in response to 2 mM fructose (17 ± 2.3%; P = 0.06). There was no difference in total cell number between MU1, 2 mM glucose, and 2 mM fructose (30.6 ± 2.2, 30.5 ± 3.7, and 32.6 ± 3.0, respectively; P ≥ 0.9) 3 replications, N = 32. Because there is very little consumption of lactate and very low levels of pyruvate are being consumed when glucose is present, it does not appear that any of these energy substrates are major players for the developing pig embryo. Future experiments should be conducted to determine other means of energy production and metabolism in these embryos. The research was funded by Food for the 21st Century.

282 GENE EXPRESSION PATTERNS AND QUALITY OF BOVINE EMBRYOS PRODUCED UNDER DIFFERENT OXYGEN CONCENTRATIONS

2007 ◽  
Vol 19 (1) ◽  
pp. 256
Author(s):  
W. J. Son ◽  
M. K. B. ◽  
Y. J. Jeong ◽  
S. Balasubramanian ◽  
S. Y. Choe ◽  
...  
Keyword(s):  
Gene Expression ◽  
Embryo Development ◽  
Expression Patterns ◽  
Cell Number ◽  
Blastocyst Stage ◽  
Total Cell ◽  
Blastocyst Development ◽  
Glut 1

Various factors are known to influence the survival and development of in vitro-produced embryos, including co-culture with somatic cells, antioxidants, and O2 tension. Studies in several species report that embryo development and quality were enhanced at low O2 concentrations. This study compared the effects of 2 O2 concentrations on IVP embryo development, embryo quality, and gene expression to those of in vivo counterparts. Cumulus–oocyte complexes were matured in vitro in TCM-199 with hormones and 10% FCS, and inseminated in TALP medium. Presumptive zygotes were cultured in SOF medium under either 5% or 20% O2 in air. In triplicate, sets of 5 embryos at the 2-cell, 4-cell, 8-cell, 16-cell, morula, and Day 7 blastocyst stages were used for analyzing the expression patterns of apoptotic (Bax and Bcl2), metabolism (Glut-1 and Glut-5), stress (Sox, Hsp70, and G6PDH), compaction (Cx43), oxidation (PRDX5, NADH, and MnSOD), and implantation (VEGF and IFN-tau) genes using real-time quantitative PCR. The expression of each gene was normalized to that of glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Statistical analysis was performed with Bonferroni and Duncan tests by ANOVA (P &lt; 0.05). Cleavage rates did not differ among groups. Blastocyst and hatched blastocyst development in 5% O2 was significantly (P &lt; 0.05) higher than in 20% O2. Total cell number of in vivo blastocysts was significantly (P &lt; 0.05) higher than that of IVP blastocysts. ICM ratio and apoptosis of in vivo blastocysts were significantly (P &lt; 0.05) lower than for IVP blastocysts. The relative abundances (RAs) of Glut-1, Glut-5, MnSOD, NADH, PRDX5, Cx43, Bcl2, and IFN-τ were significantly (P &lt; 0.05) higher in in vivo embryos, whereas the RAs of Sox, G6PDH, Hsp70, Bax, and VEGF were significantly (P &lt; 0.05) lower than for IVP counterparts. In conclusion, culture at 5% O2 concentration resulted in higher rates of development to the blastocyst stage, higher total cell numbers, and decreased apoptosis. Furthermore, differences in expression of genes including Glut-1, Glut-5, Sox, G6PDH, Hsp70, Bax, Bcl2, Cx43, PRDX5, NADH, MnSOD, VEGF, and IFN-τ may prove useful in determining optimal culture conditions. This work was supported by ARPC (204119-03-SB010), Republic of Korea.

scholarly journals Simultaneous gene quantitation of multiple genes in individual bovine nuclear transfer blastocysts

Reproduction ◽  
2007 ◽  
Vol 133 (1) ◽  
pp. 231-242 ◽  
Author(s):  
Craig Smith ◽  
Debbie Berg ◽  
Sue Beaumont ◽  
Neil T Standley ◽  
David N Wells ◽  
...  
Keyword(s):  
Gene Expression ◽  
Nuclear Transfer ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Ectopic Expression ◽  
Cell Number ◽  
Transcript Levels ◽  
Multiple Genes

During somatic cell nuclear transfer (NT), the transcriptional status of the donor cell has to be reprogrammed to reflect that of an embryo. We analysed the accuracy of this process by comparing transcript levels of four developmentally important genes (Oct4,Otx2,Ifitm3,GATA6), a gene involved in epigenetic regulation (Dnmt3a) and three housekeeping genes (β-actin, β-tubulinandGAPDH) in 21 NT blastocysts with that in genetically half-identicalin vitroproduced (IVP,n=19) andin vivo(n=15) bovine embryos. We have optimised an RNA-isolation and SYBR-green-based real-time RT-PCR procedure allowing the reproducible absolute quantification of multiple genes from a single blastocyst. Our data indicated that transcript levels did not differ significantly between stage and grade-matched zona-free NT and IVP embryos except for Ifitm3/Fragilis, which was expressed at twofold higher levels in NT blastocysts.Ifitm3expression is confined to the inner cell mass at day 7 blastocysts and to the epiblast in day 14 embryos. No ectopic expression in the trophectoderm was seen in NT embryos. Gene expression in NTand IVP embryos increased between two- and threefold for all eight genes from early to late blastocyst stages. This increase exceeded the increase in cell number over this time period indicating an increase in transcript number per cell. Embryo quality (morphological grading) was correlated to cell number for NT and IVP embryos with grade 3 blastocysts containing 30% fewer cells. However, only NT embryos displayed a significant reduction in gene expression (50%) with loss of quality. Variability in gene expression levels was not significantly different in NT, IVP orin vivoembryos but differed among genes, suggesting that the stringency of regulation is intrinsic to a gene and not affected by culture or nuclear transfer.Oct4levels exhibited the lowest variability. Analysing the total variability of all eight genes for individual embryos revealed thatin vivoembryos resembled each other much more than did NT and IVP blastocysts. Furthermore,in vivoembryos, consisting of 1.5-fold more cells, generally contained two- to fourfold more transcripts for the eight genes than did their cultured counterparts. Thus, culture conditions (in vivoversusin vitro) have greater effects on gene expression than does nuclear transfer when minimising genetic heterogeneity.

282 IMPROVED QUALITY OF PORCINE BLASTOCYSTS BY AGGREGATION OF EMBRYOS AT THE 4 - 8-CELL STAGE

2006 ◽  
Vol 18 (2) ◽  
pp. 248
Author(s):  
S.-G. Lee ◽  
C.-H. Park ◽  
D.-H. Choi ◽  
H.-Y. Son ◽  
C.-K. Lee
Keyword(s):  
Es Cells ◽  
Embryonic Stem ◽  
Transgenic Animals ◽  
Cell Number ◽  
Blastocyst Stage ◽  
Cell Stage ◽  
Vitro Fertilization

Use of blastocysts produced in vitro would be an efficient way to generate embryonic stem (ES) cells for the production of transgenic animals and the study of developmental gene regulation. In pigs, the morphology and cell number of in vitro-produced blastocysts are inferior to these parameters in their in vivo counterparts. Therefore, establishment of ES cells from blastocysts produced in vitro might be hindered by poor embryo quality. The objective of this study was to increase the cell number of blastocysts derived by aggregating 4–8-cell stage porcine embryos produced in vitro. Cumulus–oocyte complexes were collected from prepubertal gilt ovaries, and matured in vitro. Embryos at the 4–8-cell stage were produced by culturing embryos for two days after in vitro fertilization (IVF). After removal of the zona pellucida with acid Tyrode’s solution, one (1X), two (2X), and three (3X) 4–8-cell stage embryos were aggregated by co-culturing them in aggregation plates followed by culturing to the blastocyst stage. After 7 days, the developmental ability and the number of cells in aggregated embryos were determined by staining with Hoechst 33342 and propidium iodide. The percentage of blastocysts was higher in both 2X and 3X aggregated embryos compared to that of 1X and that of intact controls (Table 1). The cell number of blastocysts also increased in aggregated embryos compared to that of non-aggregated (1X) embryos and controls. This result suggests that aggregation might improve the quality of in vitro-fertilized porcine blastocysts by increasing cell numbers, thus becoming a useful resource for isolation and establishment of porcine ES cells. Further studies are required to investigate the quality of the aggregated embryos in terms of increasing the pluripotent cell population by staining for Oct-4 and to apply improved aggregation methods in nuclear-transferred (NT) porcine embryos. Table 1. Development, cell number, and ICM ratio of aggregated porcine embryos

53 EFFECT OF ADDITION OF L-CARNITINE AND CONJUGATED LINOLEIC ACID DURING BOVINE EMBRYO CULTURE ON CRYOSURVIVAL, LIPID CONTENT, AND GENE EXPRESSION

2015 ◽  
Vol 27 (1) ◽  
pp. 119
Author(s):  
A. Ruiz ◽  
P. J. Hansen ◽  
J. Block
Keyword(s):  
Gene Expression ◽  
Lipid Metabolism ◽  
Linoleic Acid ◽  
Conjugated Linoleic Acid ◽  
Lipid Content ◽  
Embryo Culture ◽  
Blastocyst Stage ◽  
Hatching Rate ◽  
Bovine Embryo

The objective was to determine the effects of addition of l-carnitine (LC) and trans-10, cis-12 conjugated linoleic acid (CLA) during bovine embryo culture on cryosurvival, lipid content, and gene expression. For all experiments, embryos were produced in vitro using abattoir-derived oocytes. Following insemination, presumptive zygotes were randomly assigned in a 2 × 2 factorial to be cultured in SOF-BE1 supplemented with or without 3.03 mM LC and 100 μM CLA until Day 7. For Exp. 1, blastocyst- and expanded-blastocyst-stage embryos (n = 777) were slow-frozen in 1.5 M ethylene glycol. Embryos were thawed and then cultured for 72 h. Re-expansion and hatching rates were recorded at 24, 48, and 72 h. There was no effect of LC on post-thaw re-expansion rates, but CLA reduced (P < 0.05) and tended (P < 0.08) to reduce re-expansion rate at 24 and 48 h, respectively (76.5 ± 2.5 v. 70.4 ± 2.5 and 79.5 ± 2.2 v. 76.0 ± 2.2, respectively). Whereas hatching rate at 72 h tended (P < 0.08) to be higher for embryos cultured with LC (67.8 ± 2.5 v. 74.4 ± 2.5), treatment with CLA reduced (P < 0.05) hatching rate at 48 h (62.3 ± 2.6 v. 54.9 ± 2.6). In Exp. 2, to determine lipid content, expanded blastocyst-stage embryos (n = 263) were harvested and stained using Nile Red. Embryos were examined for fluorescence using an epifluorescence microscope, and intensity of fluorescence per unit area was quantified using ImageJ software (NIH, Bethesda, MD, USA). There was a significant interaction (P < 0.01) between LC and CLA affecting embryo lipid content. Whereas addition of CLA during culture increased lipid, treatment with LC and the combination of LC and CLA reduced lipid (22.8 ± 1.1 v. 19.1 ± 1.1 v. 28.4 ± 1.1 v. 19.2 ± 1.2 for no additive, +LC, +CLA, and +LC and CLA, respectively). For Exp. 3, the effect of LC and CLA on the relative abundance of genes involved in lipid metabolism (ELOVL6, SCD1, SQLE, HMGCS1, CYP51A1, FDPS, FDFT1, LDLR, and SC4MOL) was determined. Pools of 5 expanded blastocyst-stage embryos from each treatment were collected across 5 replicates. The RNA was purified and synthesised into cDNA for RT-qPCR analysis. The SDHA, GAPDH, and YWAZ were used as housekeeping genes. Addition of LC during culture reduced (P < 0.05) the abundance of 4 of the 9 genes analysed (SQLE, HMGCS1, CYP51A1, and FDPS) and tended (P < 0.08) to reduce a fifth (FDFT1). In addition, there was a tendency (P < 0.08) for LC to increase the abundance of SCD1. Addition of CLA during culture had minimal effects on transcript abundance. In particular, CLA treatment reduced (P < 0.01) ELOVL6 and tended (P < 0.08) to increase SCD1. In contrast to previous studies, post-thaw cryosurvival was not significantly improved by treatment with LC or CLA. Results indicate that reduced embryo lipid content caused by LC treatment is due, in part, to an alteration in the abundance of genes involved in lipid metabolism. Further research is still necessary to determine whether in vivo survival following transfer of cryopreserved embryos can be enhanced by treatment with LC or CLA.Support was provided by USDA AFRI Grant 2010–85122–20623.

97 SUPPLEMENTATION WITH FOLATE IN VITRO INCREASES TROPHECTODERM AND TOTAL CELL NUMBER IN IN VITRO-DERIVED PORCINE BLASTOCYSTS

2012 ◽  
Vol 24 (1) ◽  
pp. 161 ◽  
Author(s):  
B. K. Redel ◽  
L. D. Spate ◽  
A. N. Brown ◽  
R. S. Prather
Keyword(s):  
Embryo Culture ◽  
Culture Medium ◽  
Transcriptional Profiling ◽  
Cell Number ◽  
Total Cell ◽  
Differential Staining ◽  
Total Cell Number ◽  
Culture Systems

It is vital that improvements are made to current culture environments because in vitro culture systems are suboptimal compared with in vivo. A previous transcriptional profiling endeavour conducted by Bauer et al. (2010 Biol. Reprod. 83, 791–798) identified hundreds of mRNA transcripts that were mis-expressed in porcine embryos fertilized in vivo and then cultured in vitro to Day 6 compared with in vivo Day-6 embryos. Enriched in the downregulated transcripts were 4 genes involved with the one carbon pool by folate KEGG pathway. This downregulation of genes involved with folate metabolism may illustrate an impaired folate homeostasis in embryos cultured in the current culture environment. The objective of this study was to determine the effects folate had on embryo development of in vitro fertilized embryos. Porcine cumulus–oocyte complexes were matured for 44 h in M199 supplemented with epidermal growth factor (EGF), FSH and LH. Oocytes with a visible polar body were selected and fertilized in modified tris buffered medium for 5 h and then placed into porcine zygote medium 3 with 0 mM, 0.2 mM, 0.4 mM and 0.8 mM folate to find the optimal concentration of folate. Twenty-eight hours post-fertilization, cleaved embryos were selected and moved into 25-μL drops of respective culture medium and cultured to Day 6 in a water-saturated atmosphere of 5% CO2, 5% O2, 90% N2, at 38.5°C. To determine the effect folate had on development, the blastocyst rate for each treatment group was measured. Results were log-transformed and analysed by using PROC GLM in SAS (SAS Institute Inc., Cary, NC). A least-significant difference post-test comparison was completed to determine if significant differences existed between treatment groups. The percentage of cleaved embryos on Day 6 that developed to blastocyst was 56.2%, 55.9%, 66.9% and 61.8% (n = 133, 149, 135 and 135) in 0 mM, 0.2 mM folate, 0.4 mM folate and 0.8 mM, respectively. The 0.4 mM folate group tended (P = 0.07) to have a higher number of cleaved embryos that developed to the blastocyst stage. Consequently, this concentration was used for all further embryo culture experiments. Differential staining was completed to compare the number of trophectoderm and inner cell mass nuclei for embryos cultured in 0 mM or 0.4 mM folate concentrations. Staining revealed that embryos cultured with folate had an increase in number of trophectoderm (29.7 ± 1.5 vs 24.4 ± 1.4 cells; P = 0.0058) and total cell (36.9 ± 1.0 vs 31.7 ± 1.0; P = 0.0007) numbers compared with embryos cultured without folate. These results illustrate that the addition of folate to current culture medium doesn't hinder development to blastocyst and by increasing trophectoderm and total cell number may give rise to better-quality in vitro-derived embryos. It is evident that using transcriptional profiling can be a great method of identifying ways to improve embryo culture systems and, in this case, supplementing with folate. Funded by Food for the 21st Century.

Effect of protein supplementation on development to the hatching and hatched blastocyst stages of cat IVF embryos

2002 ◽  
Vol 14 (5) ◽  
pp. 291 ◽  
Author(s):  
N. W. Kurniani Karja ◽  
Takeshige Otoi ◽  
Masako Murakami ◽  
Minori Yuge ◽  
Mokhamad Fahrudin ◽  
...  
Keyword(s):  
Bovine Serum ◽  
Culture Medium ◽  
Cell Number ◽  
Blastocyst Stage ◽  
Early Embryo ◽  
Protein Supplementation ◽  
Vitro Fertilization ◽  
Fetal Bovine ◽  
The Mean

The effects of protein supplementation in culture medium on development to the hatching and hatched blastocyst stages of cat in vitro-fertilized embryos were investigated. In the first experiment, presumptive zygotes derived from in vitro maturation and in vitro fertilization (IVF) were cultured in modified Earle's balanced salt solution (MK-1) supplemented with 0.4% bovine serum albumin (BSA) or 5% fetal bovine serum (FBS) for 9 days. There were no significant differences between the BSA and FBS groups with respect to the proportion of cleavage and development to the morula and blastocyst stages of zygotes. However, the presence of FBS in the medium enhanced development to the hatching blastocyst stage of zygotes compared with the BSA group (31.4% v. 7.8%). Moreover, 2.9% of zygotes cultured with FBS developed to the hatched blastocyst stage. The mean cell number of blastocysts derived from zygotes cultured with FBS was significantly higher (P&lt;0.01) than that from zygotes cultured with BSA (136.6 v.101.5). In the second experiment, embryos at the morula or blastocyst stage, which were produced by culturing in MK-1 supplemented with 0.4% BSA after IVF, were subsequently cultured in MK-1 with 0.4% BSA or 5% FBS. Significantly more morulae developed to the blastocyst (P&lt;0.05) and hatching blastocyst stages (P&lt;0.01) in the FBS group than in the BSA group (71.5% and 53.6% v. 44.9% and 6.0%, respectively). Although none of the morulae cultured with BSA developed to the hatched blastocyst stage, 11.5% of morulae cultured with FBS developed to the hatched blastocyst stage. Moreover, the proportion of development to the hatching blastocyst stage of blastocysts was significantly higher (P&lt;0.01) in the FBS group than in the BSA group (68.7% v. 9.8%). None of the blastocysts cultured with BSA developed to the hatched blastocyst stage, whereas 7.3% of blastocysts cultured with FBS developed to the hatched blastocyst stage. The results of the present study indicate that supplementation with FBS at different stages of early embryo development promotes development to the hatching and hatched blastocyst stages of cat IVF embryos.

scholarly journals Developmental and molecular correlates of bovine preimplantation embryos

Reproduction ◽  
2006 ◽  
Vol 131 (5) ◽  
pp. 895-904 ◽  
Author(s):  
Hakan Sagirkaya ◽  
Muge Misirlioglu ◽  
Abdullah Kaya ◽  
Neal L First ◽  
John J Parrish ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Methyltransferase ◽  
Expression Profiles ◽  
Expression Patterns ◽  
Blastocyst Stage ◽  
Culture Conditions ◽  
Preimplantation Embryos ◽  
Developmental Potential

Expression of embryonic genes is altered in different culture conditions, which influence developmental potential both during preimplantation and fetal development. The objective of this study was to define the effects of culture conditions on: bovine embryonic development to blastocyst stage, blastocyst cell number, apoptosis and expression patterns of a panel of developmentally important genes. Bovine embryos were culturedin vitroin three culture media containing amino acids, namely potassium simplex optimization medium (KSOMaa), Charles Rosenkrans 1 (CR1aa) and synthetic oviductal fluid (SOFaa). Apoptosis in blastocysts was determined by TUNEL assay and expression profiles of developmentally important genes were assayed by real-time PCR.In vivo-produced bovine blastocysts were used as controls for experiments determining gene expression patterns. While the cleavage rates did not differ, embryos cultured in SOFaa had higher rates of development to blastocyst stage (P< 0.05). Mean cell numbers and percentages of apoptotic cells per blastocyst did not differ among the groups. Expression of the heat shock protein 70 (Hsp70) gene was significantly up-regulated in both CR1aa and KSOMaa when compared with SOFaa (P< 0.001). DNA methyltransferase 3a (Dnmt3a) expression was higher in embryos cultured in CR1aa than in those cultured in SOFaa (P< 0.001). Expression of interferon tau (IF-τ) and insulin-like growth factor II receptor (Igf-2r) genes was significantly up-regulated in KSOMaa when compared with CR1aa (P< 0.001). Gene expression did not differ betweenin vivo-derived blastocysts and theirin vitro-derived counterparts. In conclusion, SOFaa supports higher development to blastocyst stage than KSOMaa and CR1aa, and the culture conditions influence gene expression.

scholarly journals 152EFFECT OF REPLACEMENT OF PYRUVATE/LACTATE IN CULTURE MEDIUM WITH GLUCOSE ON PREIMPLANTATION DEVELOPMENT OF PORCINE EMBRYOS IN VITRO

2004 ◽  
Vol 16 (2) ◽  
pp. 198
Author(s):  
N.W.K. Karja ◽  
S. Medvedev ◽  
D. Fuchimoto ◽  
A. Onishi ◽  
M. Iwamoto ◽  
...  
Keyword(s):  
Energy Source ◽  
Cell Number ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Culture Period ◽  
Blastocyst Formation ◽  
Cell Stage ◽  
Energy Substrates ◽  
Anova Test

Kikuchi et al. (2002 Biol. Reprod. 66, 1033–1041) reported that replacement of pyruvate and lactate with glucose, as energy substrates, at 48h of culture in IVC medium enhanced the quality of IVP porcine blastocysts. However, the exact time during early cleavage stages when the utilization of glucose as an energy source is optimal has not yet been determined. The purpose of this study was to examine the effects of glucose supplementation at different times of culture on the developmental competence of IVP porcine embryos. Porcine cumulus-oocytes complexes were matured in modified NCSU-37 solution and fertilized in vitro according to Kikuchi et al. All cultures were performed at 38.5°C, 5% O2, 5% CO2, and 90% N2. In experiment 1, after being fertilized (Day 0), putative zygotes (1158 in 6 trials) were cultured in NCSU-37 supplemented with 0.4% BSA, 0.17mM sodium pyruvate, and 2.73mM sodium lactate (IVC-pyr/lac). Embryos (30–50 in each group) were then transferred into NCSU-37 supplemented with 0.4% BSA and 5.55mM D-glucose (IVC-glu) at 24, 48, 72, 96, or 118h of culture. As control groups, putative zygotes (391) were cultured in IVC-pyr/lac or IVC-glu for the whole culture period. In experiment 2, after being fertilized, putative zygotes (543 in 4 trials, 30–50 in each group) were cultured in IVC-pyr/lac, and then were transferred into IVC-glu at 48h, 53h, 58h, or 63h of culture, because glycolytic activity of in vitro-derived porcine embryos was reported to increase around the 8-cell stage, and some embryos develop to that stage before 72h of culture in experiment 1. All embryos were cultured for 6 days, and then development to the blastocyst stage and number of cells per blastocyst were assessed. When IVF embryos were cultured in IVC pyr/lac for 24h or 48h and subsequently in IVC-glu until day 6 in experiment 1, the rates of blastocyst formation were significantly higher (P&lt;0.05, ANOVA test) than those of embryos cultured in IVC-pyr/lac for the whole culture period (24.4% and 23.0% v. 14.5%, respectively). However, when IVC pyr/lac was replaced with IVC-glu, there were no significant differences between the energy source replacement groups and the glucose-only group in terms of the proportions of cleavage, development to the blastocyst stage and mean cell number per blastocyst (P&gt;0.05, ANOVA test) (15.2%–24.4%, and 16.8%, respectively). Replacement of pyruvate and lactate with glucose at 58h of culture in experiment 2 significantly enhanced the rate of blastocyst formation (P&lt;0.05, ANOVA test) but not the mean cell number compared with zygotes in which the replacement was done at 48, 53, and 63h of culture (31.3% v. 20.6%, 20.8%, and 21.1%, respectively) (P&lt;0.05, ANOVA test). In conclusion, replacement of pyruvate and lactate with glucose as energy substrates was optimal at 58h of culture for the in vitro development of pig embryos to the blastocyst stage.

scholarly journals Effect of N-acetyl cysteine on the quality of blastocyst formation rate using cultured vitrified murine embryos

2020 ◽  
Vol 71 (3) ◽  
pp. 2315
Author(s):  
S. SIGÜENZA ◽  
I.S. ÁLVAREZ ◽  
E. MATILLA
Keyword(s):  
Embryo Culture ◽  
Formation Rate ◽  
Cell Number ◽  
Embryo Cryopreservation ◽  
Radical Scavenger ◽  
Murine Embryos ◽  
And Control

Vitrification is the best method for embryo cryopreservation although it increases endogenous reactive oxygen species (ROS) production. N-acetylcysteine (NAC) a free radical scavenger may be used for reducing ROS toxic effects. The aim of the present study is to investigate potential beneficial effects of NAC on the developmental embryo competence applying different culture conditions in vitrified-warmed 2-cell embryos derived in vivo or in vitro. Thus, 2-cell embryos were vitrified or cultured fresh in presence or absence of 1 mM of NAC during: a) the entire embryo culture, b) for 24 hours with NAC at days 1.5 (G1) or 2.5 (G2) and returned to basal embryo culture (KSOM) or c) cultured in the presence of NAC for 12 hours at day 3.5 (G3). Despite NAC addition to fresh or vitrified embryos produced in vivo or by IVF, blastocyst rates remained unchanged. In vitrified-warmed IU or IVF-derived embryos, total cell number varied when NAC was added at day 1.5 although differences were not significant (60.1 ± 1.9 vs. 59.4 ± 1.3 for IU G1 and control respectively; and 59.3 ± 1.6 and 52.6 ± 3.0 IVF G1 and control respectively; mean cell number ± SEM, p > 0.05). It seems that the embryo culture medium supplementation with 1 mM of NAC in the first day after vitrification of development improves blastocyst quality of murine embryos and does not exert any beneficial effect at oyher culture points.

scholarly journals MCRS1 is essential for epiblast development during early mouse embryogenesis

Reproduction ◽  
2020 ◽  
Vol 159 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Wei Cui ◽  
Agnes Cheong ◽  
Yongsheng Wang ◽  
Yuran Tsuchida ◽  
Yong Liu ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Embryonic Stem ◽  
Cell Number ◽  
Blastocyst Stage ◽  
Histone H4 ◽  
Histone H4 Acetylation ◽  
Early Mouse

Microspherule protein 1 (MCRS1, also known as MSP58) is an evolutionarily conserved protein that has been implicated in various biological processes. Although a variety of functions have been attributed to MCRS1 in vitro, mammalian MCRS1 has not been studied in vivo. Here we report that MCRS1 is essential during early murine development. Mcrs1 mutant embryos exhibit normal morphology at the blastocyst stage but cannot be recovered at gastrulation, suggesting an implantation failure. Outgrowth (OG) assays reveal that mutant blastocysts do not form a typical inner cell mass (ICM) colony, the source of embryonic stem cells (ESCs). Surprisingly, cell death and histone H4 acetylation analysis reveal that apoptosis and global H4 acetylation are normal in mutant blastocysts. However, analysis of lineage specification reveals that while the trophoblast and primitive endoderm are properly specified, the epiblast lineage is compromised and exhibits a severe reduction in cell number. In summary, our study demonstrates the indispensable role of MCRS1 in epiblast development during early mammalian embryogenesis.

Sign in / Sign up

Export Citation Format

Share Document