EDTA stimulates cleavage stage bovine embryo development in culture but inhibits blastocyst development and differentiation

Abstract

Culture of bovine zygotes in medium SOFaa supplemented with 100 μM EDTA significantly increased cleavage rates during the first 72 hr of development compared to development in SOFaa. However, continued culture in the presence of EDTA for a further 72 hr (total of 6 days of culture) resulted in significantly reduced development to the morulae/blastocyst and blastocyst stages compared to culture without EDTA. Highest rates of development to the morulae/blastocyst stage (56.5%) and to the blastocyst stage (43.2%) were achieved when zygotes were cultured for 72 hr with EDTA before transfer to medium SOFaa without EDTA. Resultant blastocysts also had significantly increased blastocyst cell number and ICM cell number compared to those cultured without EDTA in the first 72 hr. EDTA was shown to inhibit glycolytic activity of the cleavage stage embryo, thereby preventing the premature stimulation of glycolysis and enhancing development. However, EDTA should not be used for the later stage embryo as the inhibition of glycolysis reduces energy production at the blastocyst stage and significantly inhibits inner cell mass development. Mol. Reprod. Dev. 57:256–261, 2000. © 2000 Wiley‐Liss, Inc.

Effect of different sequential and two‐step culture systems on the development, quality, and RNA expression profile of bovine blastocysts produced in vitro

“…These results are also in disagreement to those described previously by Gardner et al (2000), who found that culturing bovine zygotes in the presence of EDTA at later stages of development inhibited blastocysts formation and reduced the quality and cell numbers, although important differences in the concentration of EDTA and in other components of the formulation of each culture medium make the comparison difficult.…”

Effect of different sequential and two‐step culture systems on the development, quality, and RNA expression profile of bovine blastocysts produced in vitro

“…These results are also in disagreement to those described previously by Gardner et al (2000), who found that culturing bovine zygotes in the presence of EDTA at later stages of development inhibited blastocysts formation and reduced the quality and cell numbers, although important differences in the concentration of EDTA and in other components of the formulation of each culture medium make the comparison difficult.…”

Differential Gene Expression Profile in Bovine Blastocysts Resulting from Hyperglycemia Exposure During Early Cleavage Stages1

“…This observation is in agreement with previous publications that have shown that increased glucose concentration in the medium blocks early cleavage development [16,25]. This developmental block reflects a phenomenon known as the Crabtree effect, whereby high intracellular glucose stimulates glycolysis that perturbs oxidative phosphorylation (OX-PHOS) by altering mitochondrial metabolism [14,[25][26][27][28]. When 5 mM glucose was used, early cleavage bovine zygotes exhibited developmental plasticity, as seen by the ability to reach 8-16 cells.…”

Impact of adding 5.5 mM glucose to SOF medium on the development, metabolism and quality of in vitro produced bovine embryos from the morula to the blastocyst stage

“…Inhibition of glycolysis at the morula and blastocyst stages, for example by adding EDTA to the culture medium, is thought to decrease the number of ICM cells in mouse and bovine embryos Gardner et al, 2000), while stimulating glycolysis increases blastocyst cell number (Thompson et al, 2000). In our study however, adding glucose did not affect the ratio of ICM to TE cells on day 7, while a slight decrease was observed in total cell numbers in comparison with embryos grown without added glucose.…”

Effect of different sequential and two‐step culture systems on the development, quality, and RNA expression profile of bovine blastocysts produced in vitro

“…These results are also in disagreement to those described previously by Gardner et al (2000), who found that culturing bovine zygotes in the presence of EDTA at later stages of development inhibited blastocysts formation and reduced the quality and cell numbers, although important differences in the concentration of EDTA and in other components of the formulation of each culture medium make the comparison difficult.…”

Differential Gene Expression Profile in Bovine Blastocysts Resulting from Hyperglycemia Exposure During Early Cleavage Stages1

“…This observation is in agreement with previous publications that have shown that increased glucose concentration in the medium blocks early cleavage development [16,25]. This developmental block reflects a phenomenon known as the Crabtree effect, whereby high intracellular glucose stimulates glycolysis that perturbs oxidative phosphorylation (OX-PHOS) by altering mitochondrial metabolism [14,[25][26][27][28]. When 5 mM glucose was used, early cleavage bovine zygotes exhibited developmental plasticity, as seen by the ability to reach 8-16 cells.…”

Impact of adding 5.5 mM glucose to SOF medium on the development, metabolism and quality of in vitro produced bovine embryos from the morula to the blastocyst stage

“…Inhibition of glycolysis at the morula and blastocyst stages, for example by adding EDTA to the culture medium, is thought to decrease the number of ICM cells in mouse and bovine embryos Gardner et al, 2000), while stimulating glycolysis increases blastocyst cell number (Thompson et al, 2000). In our study however, adding glucose did not affect the ratio of ICM to TE cells on day 7, while a slight decrease was observed in total cell numbers in comparison with embryos grown without added glucose.…”

Effect of different sequential and two‐step culture systems on the development, quality, and RNA expression profile of bovine blastocysts produced in vitro

“…These results are also in disagreement to those described previously by Gardner et al (2000), who found that culturing bovine zygotes in the presence of EDTA at later stages of development inhibited blastocysts formation and reduced the quality and cell numbers, although important differences in the concentration of EDTA and in other components of the formulation of each culture medium make the comparison difficult.…”

Differential Gene Expression Profile in Bovine Blastocysts Resulting from Hyperglycemia Exposure During Early Cleavage Stages1

“…This observation is in agreement with previous publications that have shown that increased glucose concentration in the medium blocks early cleavage development [16,25]. This developmental block reflects a phenomenon known as the Crabtree effect, whereby high intracellular glucose stimulates glycolysis that perturbs oxidative phosphorylation (OX-PHOS) by altering mitochondrial metabolism [14,[25][26][27][28]. When 5 mM glucose was used, early cleavage bovine zygotes exhibited developmental plasticity, as seen by the ability to reach 8-16 cells.…”

Impact of adding 5.5 mM glucose to SOF medium on the development, metabolism and quality of in vitro produced bovine embryos from the morula to the blastocyst stage

“…Inhibition of glycolysis at the morula and blastocyst stages, for example by adding EDTA to the culture medium, is thought to decrease the number of ICM cells in mouse and bovine embryos Gardner et al, 2000), while stimulating glycolysis increases blastocyst cell number (Thompson et al, 2000). In our study however, adding glucose did not affect the ratio of ICM to TE cells on day 7, while a slight decrease was observed in total cell numbers in comparison with embryos grown without added glucose.…”