title: Effect of varying glucose and glucosamine concentration in vitro on mouse oocyte maturation and developmental competence.
abstract: The effects of hyper- and hypo-glycaemic conditions during the in vitro maturation of mouse cumulus-oocyte complexes on developmental competence were examined, with an emphasis on the role of the hexosamine biosynthesis pathway. A low (1 mM) glucose concentration achieved optimal oocyte competence (3-fold higher blastocyst development rate compared with high (30 mM) glucose, P<0.05). In addition, glucose supplementation during only the first hour after release from the follicle was necessary and sufficient to support oocyte maturation and embryo development to the blastocyst stage. Glucosamine (a known hyperglycaemic mimetic and specific activator of the hexosamine pathway) was able to substitute for glucose during this first hour, indicating that flux through the hexosamine pathway is essential for oocyte competence. In the absence of glucose throughout the maturation period, glucosamine was not able to increase developmental competence, and at higher concentrations (2.5 and 5 mM) had a detrimental effect on MII and blastocyst development rates, compared with controls (P<0.05). These experiments underscore the importance of glucose metabolic pathways during in vitro maturation and support the concept that excess flux through the hexosamine pathway has detrimental consequences.
authors.affiliation: The Robinson Institute, Research Centre for Reproductive Health, School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, SA 5005, Australia.
authors.forename: L A
authors.initials: LA
authors.lastname: Frank
authors.forename: M L
authors.initials: ML
authors.lastname: Sutton-McDowall
authors.forename: D L
authors.initials: DL
authors.lastname: Russell
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: D K
authors.initials: DK
authors.lastname: Feil
authors.forename: R B
authors.initials: RB
authors.lastname: Gilchrist
authors.forename: J G
authors.initials: JG
authors.lastname: Thompson
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology*; D002970:Cleavage Stage, Ovum / Q000166:cytology / Q000378:metabolism; D003433:Crosses, Genetic; D016895:Culture Media, Serum-Free / Q000378:metabolism; D054885:Cumulus Cells / Q000502:physiology; D046149:Embryo Culture Techniques; D047108:Embryonic Development; D005260:Female; D005307:Fertilization in Vitro; D005944:Glucosamine / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D059471:In Vitro Oocyte Maturation Techniques; D008297:Male; D008677:Metaphase; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D009866:Oogenesis; D009994:Osmolar Concentration; D013084:Sperm-Ovum Interactions
chemical_list: D016895:Culture Media, Serum-Free; D005947:Glucose; D005944:Glucosamine