Enhanced glycolysis after maturation of bovine oocytes in vitro is associated with increased developmental competence

Absence of cumulus cells during in vitro maturation affects lipid metabolism in bovine oocytes

“…It was reported that intracellular lipids are a very important endogenous source of energy in the oocyte during maturation in different mammalian species, including bovine (51,68), in addition to glucose and pyruvate uptake, which are considered key substrates to provide energy for oocyte maturation (39,70). In fact, in our study using Nile Red, we observed a decrease of intracellular lipid contents in the oocytes after IVM compared with IO, and this was in concordance with other studies reporting lower TAG and total cholesterol content in mature oocytes than in IO (21,37).…”

Energy substrate requirement for in vitro maturation of oocytes from unstimulated adult rhesus monkeys

“…We, therefore, conclude that glucose conversion into pyruvate or lactate was not the only role of glucose for oocyte cytoplasmic maturation. In agreement with this, recent studies have revealed the importance for oocyte maturation of glucose metabolism via glycolysis and the pentose phosphate pathway (Tsutsumi et al, 1994;Downs et al, 1998;Krisher and Bavister, 1999).…”

“…Pyruvate, glucose, and lactate, the``energy substrate triad,'' impact in vitro development from oocyte maturation through blastocyst formation in many mammalian species (Kane, 1972;Bae and Foote, 1975;Bavister, 1995). For example, oocyte nuclear maturation requires pyruvate which can either be provided in the culture medium or converted from lactate or glucose (Leese and Barton, 1985;Downs and Mastropolo, 1994), while glucose is vital for cytoplasmic maturation of bovine oocytes (Rose-Hellekant et al, 1998;Krisher and Bavister, 1999). For the ®rst time, our results have demonstrated that, of these three substrates, glucose alone is adequate and necessary for optimal in vitro cytoplasmic maturation of oocytes from unstimulated rhesus monkeys.…”

Sistema De Cultivo Para Mejorar La Viabilidad De Embriones Bovinos Producidos in Vitro

“…These effects are not surprising, as protein absence can negatively impact embryo development and cell counts in group embryo culture (Krisher et al 1999;Orsi and Leese 2004). In cows, beneficial effects of protein are observed preferentially in long-term culture in vitro, whereby the absence of protein is clearly detrimental, particularly in the second part of the culture (4 days; Krisher et al 1999;Orsi and Leese 2004). Similar studies proposed that post-compaction stages would require more protein than earlier stages , consistent with our current results and with previous work (Gómez et al2014).…”