A potential role for triglyceride as an energy source during bovine oocyte maturation and early embryo development

Abstract

The potential role of endogenous triglyceride in bovine oocyte maturation and preimplantation development has been investigated. Bovine immature oocytes were recovered from abattoir-derived ovaries, matured and fertilised in vitro and the zygotes grown to the blastocyst stage in SOFaaBSA. Methyl palmoxirate (MP) blocks the oxidation of fatty acids by inhibiting mitochondrial carnitine palmitoyltransferase A. The development of zygotes exposed to MP during oocyte maturation, and of zygotes exposed to MP during embryo culture has been assessed in terms of oxygen consumption by oocytes and embryos during a 4-6 hr incubation period in the presence of MP and as blastocyst formation and cell number. Immature oocytes exposed to MP during maturation had reduced capacity to form blastocysts after fertilisation; the same effect was apparent, but to a lesser extent, in zygotes exposed to MP during embryo development. Oxygen consumption values of oocytes and blastocysts in the absence of exogenous substrates were similar to those in control medium containing nutrients. MP-inhibited oxygen consumption of immature oocytes, mature oocytes, cleavage stages embryos and blastocysts by 64, 45, 12 and 13%, respectively. The data are consistent with a role for triglyceride as a key energy source during bovine oocyte maturation and potentially, during preimplantation embryo development.

Characterisation of endometrial gene expression and metabolic parameters in beef heifers yielding viable or non-viable embryos on Day 7 after insemination

“…As previous studies (Ferguson and Leese 2006) have shown that triacylglycerides can be used as an energy source in early embryonic development up to blastocyst stage, this could have contributed to the decreased fertility in heifers with retarded embryos.…”

“…The production of prostaglandin F2 (PGF2) is responsible for luteolysis and prostaglandin E 2 (PGE 2 ) is involved in maternal recognition of pregnancy (Arosh et al 2002;Shelton et al 1990) and as such these pathways are of major importance in early embryonic development. Triglycerides are not only important in membrane synthesis but are also suggested to have a role in early embryonic development as an energy source (Ferguson and Leese 2006;Forde et al 2009a).…”

“…Triglycerides are not only important for membrane synthesis but are also suggested to have a major role in both oocyte maturation and early embryo development as an energy source (Ferguson and Leese 2006).…”

A suplementação alimentar com ácidos graxos insaturados melhora a qualidade do sêmen criopreservado de búfalos (Bubalus bubalis) pós descongelação

“…e que possui, entre outros lipídeos, o ácido linoleico (ω-6) em sua composição (NORHAIZAN et al, 2013). No metabolismo animal, os UFAs são importantes no processo reprodutivo, especificamente na produção de esteroides (WANG et al, 2003), para a fluidez nas membranas plasmáticas do espermatozoide e oócito, nas mudanças no padrão de receptores de ligação (WATHES; ABAYASEKARA; AITKEN, 2007), como fonte de energia durante a maturação dos oócitos e no desenvolvimento embrionário após a implantação (FERGUSON;LEESE, 2006). O principal ácido graxo encontrado nos espermatozoides é o ácido linolênico (ω-3), sendo que o ácido docosahexaenoico (DHA), um derivado ω-3, tem importante papel na manutenção da integridade da membrana plasmática e na motilidade espermática, bem como confere maior criorresistência às células (ROBINSON et al, 2006).…”

Carnitine content in the follicular fluid and expression of the enzymes involved in beta oxidation in oocytes and cumulus cells

“…Even if the lipid content of the mouse oocyte is weak (like in human), when compared to the pig and the cow, beta oxidation seems essential for meiotic resumption [5] and oocyte competence [6,7]. Its role in early pre-implantation development seems relevant in mouse [6][7][8] and bovine [9]. In terms of energy yields, one molecule of glucose forms in theory (maximum value) 38 moles of ATP for 106 ATP formed with palmitate, but with a higher formation of Reactive oxygen species (ROS).…”