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

Abstract

Although toxic for early stages of embryo development, glucose is a physiological metabolic substrate at the morula and blastocyst stages. We evaluated the effect of adding 5.5 mM glucose from the morula stage on bovine blastocyst development and quality. In vitro matured and fertilised bovine oocytes were cultured in modified Synthetic Oviduct Fluid medium containing 5% fetal calf serum, but without added glucose, up to day 5 post-insemination (pi). Morulae were selected and further cultured in the presence or absence of 5.5 mM glucose. Blastocyst and hatched blastocyst rates were recorded. Oxygen, glucose and pyruvate uptakes as well as lactate release were evaluated. The quality of the resulting blastocysts was evaluated by the cell allocation to the inner cell mass (ICM) and trophectoderm (TE) and by the apoptotic index. Adding glucose increased the blastocyst rate at day 8 pi (80% vs 65%) but had no impact on hatching rate (25% vs 28%). A 22% decrease in oxygen uptake was observed in the presence of glucose, concomitant with an increase in lactate release, although no change was observed in pyruvate uptake. A slight decrease in blastocyst cell number was observed at day 7 in the presence of glucose while neither the ICM/TE cell ratio nor the apoptotic index were affected. In conclusion, adding 5.5 mM glucose from the morula stage has a limited impact on blastocyst rate and quality although important modifications were observed in embryo metabolism. It remains to be determined whether those modifications could influence embryo viability after transfer.

Metabolites Secreted by Bovine Embryos In Vitro Predict Pregnancies That the Recipient Plasma Metabolome Cannot, and Vice Versa

“…When using biomarkers from two sides (i.e., embryo and recipient) shown in most cases, there is more predictive power at birth than the use of each biomarker as a single predictor. This was accompanied by improved statistical significance and predictive power within the F1 score, especially with the use of embryonic stages (only possible within the Holstein cohort), in line with the metabolic differences found within embryonic stages by other authors [80,81,82,83].…”

Metabolites Secreted by Bovine Embryos In Vitro Predict Pregnancies That the Recipient Plasma Metabolome Cannot, and Vice Versa

“…When using biomarkers from two sides (i.e., embryo and recipient) shown in most cases, there is more predictive power at birth than the use of each biomarker as a single predictor. This was accompanied by improved statistical significance and predictive power within the F1 score, especially with the use of embryonic stages (only possible within the Holstein cohort), in line with the metabolic differences found within embryonic stages by other authors [80,81,82,83].…”

Use of a Culture Medium (McCoy®), as a Method for Evaluating Bos indicus × Bos taurus Embryos

“…In addition, 10% of the embryos advanced in their stage of development. Similarly, 60% of fair embryos kept an analogous development indicative of healthy cells (Grisart et al., ; Shoukir et al., ; Donnay et al., ; Merton et al., ). On the other hand, 26% of good embryos and 40% of fair embryos could not keep their viability during culture, confirming previous findings indicating the existence of metabolically abnormal embryos, which were seemingly healthy at the morphological evaluation (Rondeau et al., ).…”

Time-dependent O2 consumption patterns determined optimal time ranges for selecting viable human embryos

“…Hardy et al described the measurement of pyruvate uptake before embryo transfer as a valuable new criterion for the selection of viable embryos that reached blastocyst stage. They observed that the pyruvate uptake in arrested embryos was significantly lower than for those embryos which developed to the blastocyst stage (66,67). However, to date whether the human embryo OC varies during early preimplantation development has been unclear.…”

Metabolites Secreted by Bovine Embryos In Vitro Predict Pregnancies That the Recipient Plasma Metabolome Cannot, and Vice Versa

“…When using biomarkers from two sides (i.e., embryo and recipient) shown in most cases, there is more predictive power at birth than the use of each biomarker as a single predictor. This was accompanied by improved statistical significance and predictive power within the F1 score, especially with the use of embryonic stages (only possible within the Holstein cohort), in line with the metabolic differences found within embryonic stages by other authors [80,81,82,83].…”

Use of a Culture Medium (McCoy®), as a Method for Evaluating Bos indicus × Bos taurus Embryos

“…In addition, 10% of the embryos advanced in their stage of development. Similarly, 60% of fair embryos kept an analogous development indicative of healthy cells (Grisart et al., ; Shoukir et al., ; Donnay et al., ; Merton et al., ). On the other hand, 26% of good embryos and 40% of fair embryos could not keep their viability during culture, confirming previous findings indicating the existence of metabolically abnormal embryos, which were seemingly healthy at the morphological evaluation (Rondeau et al., ).…”

Time-dependent O2 consumption patterns determined optimal time ranges for selecting viable human embryos

“…Hardy et al described the measurement of pyruvate uptake before embryo transfer as a valuable new criterion for the selection of viable embryos that reached blastocyst stage. They observed that the pyruvate uptake in arrested embryos was significantly lower than for those embryos which developed to the blastocyst stage (66,67). However, to date whether the human embryo OC varies during early preimplantation development has been unclear.…”

Metabolites Secreted by Bovine Embryos In Vitro Predict Pregnancies That the Recipient Plasma Metabolome Cannot, and Vice Versa

“…When using biomarkers from two sides (i.e., embryo and recipient) shown in most cases, there is more predictive power at birth than the use of each biomarker as a single predictor. This was accompanied by improved statistical significance and predictive power within the F1 score, especially with the use of embryonic stages (only possible within the Holstein cohort), in line with the metabolic differences found within embryonic stages by other authors [80,81,82,83].…”

Use of a Culture Medium (McCoy®), as a Method for Evaluating Bos indicus × Bos taurus Embryos

“…In addition, 10% of the embryos advanced in their stage of development. Similarly, 60% of fair embryos kept an analogous development indicative of healthy cells (Grisart et al., ; Shoukir et al., ; Donnay et al., ; Merton et al., ). On the other hand, 26% of good embryos and 40% of fair embryos could not keep their viability during culture, confirming previous findings indicating the existence of metabolically abnormal embryos, which were seemingly healthy at the morphological evaluation (Rondeau et al., ).…”

Time-dependent O2 consumption patterns determined optimal time ranges for selecting viable human embryos

“…Hardy et al described the measurement of pyruvate uptake before embryo transfer as a valuable new criterion for the selection of viable embryos that reached blastocyst stage. They observed that the pyruvate uptake in arrested embryos was significantly lower than for those embryos which developed to the blastocyst stage (66,67). However, to date whether the human embryo OC varies during early preimplantation development has been unclear.…”