Effects of oocyte quality, oxygen tension, embryo density, cumulus cells and energy substrates on cleavage and morula/blastocyst formation of bovine embryos

Khurana, N.K.; Niemann, Heinrich

doi:10.1016/s0093-691x(00)00387-3

Cited by 134 publications

(77 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In addition, we checked transcript levels relative to the housekeeping gene GAPDH, and thus, we expect that the effects of freezing and thawing would not change our results. It has been reported that there was a significant difference between the metabolism pathways of in vitroproduced and in vivo-developed bovine embryos (Khurana & Niemann 2000). However, in the present study the expression of Glut-1 did not differ significantly among the four groups, which reflects the fact that this isoform might not play a crucial role in embryonic glucose uptake from the environment.…”

Section: Discussioncontrasting

confidence: 81%

Developmental and molecular correlates of bovine preimplantation embryos

Sağırkaya

Mısırlıoğlu

Kaya³

et al. 2006

Reproduction

View full text Add to dashboard Cite

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 cultured in vitro in 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-t) 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 between in vivo-derived blastocysts and their in vitro-derived counterparts. In conclusion, SOFaa supports higher development to blastocyst stage than KSOMaa and CR1aa, and the culture conditions influence gene expression. Reproduction (2006) 131 895-904

show abstract

Section: Discussioncontrasting

confidence: 81%

Developmental and molecular correlates of bovine preimplantation embryos

Sağırkaya

Mısırlıoğlu

Kaya³

et al. 2006

Reproduction

View full text Add to dashboard Cite

show abstract

“…2c) was indicative of the stress conditions. High lactate production has been reported earlier as a result of stress response of the embryos under suboptimal culture conditions [40]. In the present study change in the culture environment from 20 to 5 % O 2 resulted in drastic reduction in LDH expression both in oocytes and embryos (Figs.…”

Section: Discussionsupporting

confidence: 76%

Expression pattern of glucose metabolism genes correlate with development rate of buffalo oocytes and embryos in vitro under low oxygen condition

Kumar

Verma²,

Kumar³

et al. 2015

J Assist Reprod Genet

View full text Add to dashboard Cite

Purpose This study evaluates the effect of low oxygen conditions (5 Vs 20 %) on buffalo embryo development. Expression patterns of key glucose metabolism genes (HK, PFK, LDH, PDH, G6PDH and Glut1) were assessed in buffalo oocytes and embryos cultured at 5 and 20 % oxygen and correlated with development rate. Methods Maturation rate was observed by determining MII stages by Aceto-orcein method and blastocyst formation was observed at 7 day post insemination (dpi). Expression levels of genes were determined by real time PCR in oocytes / embryos at 5 and 20 % O 2 .Results Oocyte maturation and blastocyst formation rates were significantly higher at 5 % O 2 as compared to 20 % O 2 (P<0.05). The expression pattern of glycolytic genes (HK, PFK and G6PDH) indicated that oocytes and embryos under 5 % O 2 tend to follow anaerobic glycolysis and pentose phosphate pathways to support optimum embryo development. Under 20 % O 2 , oocytes and embryos had high expression of PDH indicating higher oxidative phosphorylation. Further, less G6PDH expression at 20 % O 2 was indicative of lower pentose phosphate activity. Higher expression of LDH was observed in oocytes and embryos under 20 % O 2 indicating sub-optimal culture conditions. High Glut1 activity was observed in the oocytes / embryos at 5 % O 2 , indicative of high glucose uptake correlating with high expression of glycolytic genes. Conclusion The expression patterns of glucose metabolism genes could be a valuable indicator of the development potential of oocytes and embryos. The study indicates the importance of reduced oxygen conditions for production of good quality embryos.

show abstract

“…However, if single embryo culture is associated with a low embryo density (embryo number: medium volume ratio), the development in this situation is handicapped indicated by low blastocyst rates, low cell numbers and decreased production of interferon-t (O'Doherty et al 1997, Larson & Kubisch 1999, Khurana & Niemann 2000. Thus, embryo density that determines the interaction of embryonic factors in the microenvironment seems to be an important factor for the effectiveness of bovine vitro culture (Fujita et al 2006, Nagao et al 2008.…”

Section: Introductionmentioning

confidence: 99%

Effect of the microenvironment and embryo density on developmental characteristics and gene expression profile of bovine preimplantative embryos cultured in vitro

Hoelker¹,

Rings²,

Lund³

et al. 2009

Reproduction

View full text Add to dashboard Cite

The Well of the Well (WOW) system has been developed to culture embryos in small groups or to track the development of single embryos. In the present study, we aimed to examine the effects of the microenvironment provided by the WOW system and embryo density on developmental rates, embryo quality and preimplantative gene expression profile of the resulting embryos. Embryos cultured in a group of 16 reached the blastocyst stage at a significantly lower level than zygotes cultured in a group of 50 (22.2 vs 30.3%), whereas zygotes cultured in WOW were able to compensate against low embryo densities, reaching a blastocyst rate as high as embryos cultured in a group of 50 (31.3 vs 30.3%). Moreover, embryos derived from WOW culture did not differ in terms of differential cell counts and apoptotic cell index compared with controls. The gene expression analysis revealed 62 transcripts to be upregulated and 33 transcripts to be downregulated by WOW culture. Comparing the in vivo derived blastocysts with the blastocysts derived from WOW culture, and group culture, expression of ATP5A1, PLAC8 and KRT8 was more similar to the embryos derived from WOW culture, whereas expression of S100A10 and ZP3 genes was more similar to blastocysts cultured in a group. In conclusion, microenvironment as well as embryo density significantly affected developmental rates. While subsequent blastocysts did not differ in terms of differential cell counts and apoptotic cell index, significant differences were observed in terms of the relative abundance of transcripts in the resulting embryos.

show abstract

Effects of oocyte quality, oxygen tension, embryo density, cumulus cells and energy substrates on cleavage and morula/blastocyst formation of bovine embryos

Cited by 134 publications

References 59 publications

Developmental and molecular correlates of bovine preimplantation embryos

Developmental and molecular correlates of bovine preimplantation embryos

Expression pattern of glucose metabolism genes correlate with development rate of buffalo oocytes and embryos in vitro under low oxygen condition

Effect of the microenvironment and embryo density on developmental characteristics and gene expression profile of bovine preimplantative embryos cultured in vitro

Contact Info

Product

Resources

About