A Simple Approach for COnsumption and RElease (CORE) Analysis of Metabolic Activity in Single Mammalian Embryos

Abstract

Non-invasive assay of the consumption and release of metabolites by individual human embryos could allow selection at the cleavage stage of development and facilitate Single Embryo Transfer in clinical IVF but will require simple, high throughput, sensitive methods applicable to small volume samples.A rapid, simple, non-invasive method has therefore been devised using a standard fluorescence plate reader, and used to measure the consumption of pyruvate and glucose, and release of lactate by single bovine embryos at all stages of preimplantation development in culture; amino acid profiles have been determined using HPLC.Early embryos with an ‘intermediate’ level (6.14±0.27 pmol/embryo/h) of pyruvate uptake were associated with the highest rate (68.3%) of blastocyst development indicating that a mid “optimum” range of pyruvate consumption correlates with high viability in this bovine model.

Biological optimization, the Goldilocks principle, and how much islagomin the preimplantation embryo

“…These data were also chosen because they are quite detailed and include prospective as well as retrospective studies. Guerif et al () conducted two types of experiments in which bovine embryos were produced in an identical manner, via in vitro fertilization of in vitro‐matured immature oocytes obtained from abattoir ovaries.…”

“…These data were also chosen because they are quite detailed and include prospective as well as retrospective studies. Guerif et al (2013) conducted two types of experiments in which bovine embryos were produced in an identical manner, via in vitro fertilization of in vitro-matured immature oocytes obtained from abattoir ovaries. Experiment I. Zygotes (fertilized eggs) were allowed to develop to the 2-cell stage before being incubated individually in 5 ml of culture medium for 24 hr under an environment of 5% CO 2 , 5% O 2 , 90% N 2 .…”

“…The difficulty underlying this type of experiment is that bovine (as well as ovine and porcine) embryos are less viable if cultured singly in vitro, especially in extended culture; they prefer to be grown in groups (Stokes et al, 2005;Gopichandran and Leese, 2006). This problem was overcome by Guerif et al (2013). Experiment II.…”

Soluble Ligands and Their Receptors in Human Embryo Development and Implantation

“…This technique has been successfully applied to clinical IVF embryos to predict blastocyst quality before selection for transfer (314). For convenience, the same reactions can also be performed in a microplate format, owing to the high metabolic rate of human embryos (315).…”

MEKC‐LIF method for analysis of amino acids after on‐capillary derivatization by transverse diffusion of laminar flow profiles mixing of reactants for assessing developmental capacity of human embryos after in vitro fertilization

“…The scoring system is mostly subjective in nature, which makes it difficult to standardize. As a result, the discovery of biomarkers which can be quantified (thus being more objective) has led to focusing on the levels of genomics , transcriptomics , proteomics , and metabolomics . However it must be highlighted that in this moment the morphological evaluation by light microscopy remains the primary approach of embryo assessment during IVF cycles .…”