Metabolism of the viable mammalian embryo: quietness revisited

TY - JOUR

T1 - Metabolism of the viable mammalian embryo: quietness revisited

AU - Leese, Henry J.

AU - Baumann, Christoph G.

AU - Brison, Daniel R.

AU - McEvoy, Tom G.

AU - Sturmey, Roger G.

PY - 2008/12

Y1 - 2008/12

N2 - This review examines the 'Quiet Embryo Hypothesis' which proposes that viable preimplantation embryos operate at metabolite or nutrient turnover rates distributed within lower ranges than those of their less viable counterparts. The 'quieter' metabolism consistent with this hypothesis is considered in terms of (i) 'functional' quietness; the contrasting levels of intrinsic metabolic activity in different cell types as a consequence of their specialized functions, (ii) inter-individual embryo/cell differences in metabolism and (iii) loss of quietness in response to environmental stress. Data are reviewed which indicate that gametes and early embryos function in vivo at a lower temperature than core body temperature, which could encourage the expression of a quiet metabolism. We call for research to determine the optimum temperature for mammalian gamete/embryo culture. The review concludes by examining the key role of reactive oxygen species, which can induce molecular damage, trigger a cellular stress response and lead to a loss of quietness.

AB - This review examines the 'Quiet Embryo Hypothesis' which proposes that viable preimplantation embryos operate at metabolite or nutrient turnover rates distributed within lower ranges than those of their less viable counterparts. The 'quieter' metabolism consistent with this hypothesis is considered in terms of (i) 'functional' quietness; the contrasting levels of intrinsic metabolic activity in different cell types as a consequence of their specialized functions, (ii) inter-individual embryo/cell differences in metabolism and (iii) loss of quietness in response to environmental stress. Data are reviewed which indicate that gametes and early embryos function in vivo at a lower temperature than core body temperature, which could encourage the expression of a quiet metabolism. We call for research to determine the optimum temperature for mammalian gamete/embryo culture. The review concludes by examining the key role of reactive oxygen species, which can induce molecular damage, trigger a cellular stress response and lead to a loss of quietness.

KW - INNER CELL MASS

KW - BOVINE BLASTOCYSTS

KW - ENERGY-METABOLISM

KW - MOUSE BLASTOCYST

KW - GENE-EXPRESSION

KW - PREIMPLANTATION EMBRYOS

KW - REPRODUCTIVE-BIOLOGY

KW - OVARIAN TISSUES

KW - PYRUVATE UPTAKE

KW - PIG OOCYTES

UR - http://www.scopus.com/inward/record.url?scp=58249113941&partnerID=8YFLogxK

U2 - 10.1093/molehr/gan065

DO - 10.1093/molehr/gan065

M3 - Article

C2 - 19019836

SN - 1360-9947

VL - 14

SP - 667

EP - 672

JO - Molecular human reproduction

JF - Molecular human reproduction

IS - 12

ER -