RESUMO
The study of early embryo metabolism has fascinated researchers in the field for nearly a century. Herein, we give a brief account of the general features of embryo metabolism and some consideration of the research performed to reach such conclusions. It is becoming increasingly obvious that metabolism informs many fate decisions and outcomes beyond ATP generation, such as DNA methylation, Reactive Oxygen Species generation and cell signaling. We discuss the reasons for studying metabolism in the face of our current knowledge of the effect that the culture environment on the developing embryo and the downstream effects that can cause. The study of in vitro embryo metabolism can also give us insight into developmental perturbations in vivo. The strengths And limitations of the methods we use to study metabolism are reviewed with reference to species-specific fundamental biology and plasticity and we discuss what the future holds for metabolic studies and the unanswered questions that remain.
Assuntos
Feminino , Animais , Embrião de Mamíferos/metabolismo , Implantação do Embrião , Trifosfato de AdenosinaRESUMO
The study of early embryo metabolism has fascinated researchers in the field for nearly a century. Herein, we give a brief account of the general features of embryo metabolism and some consideration of the research performed to reach such conclusions. It is becoming increasingly obvious that metabolism informs many fate decisions and outcomes beyond ATP generation, such as DNA methylation, Reactive Oxygen Species generation and cell signaling. We discuss the reasons for studying metabolism in the face of our current knowledge of the effect that the culture environment on the developing embryo and the downstream effects that can cause. The study of in vitro embryo metabolism can also give us insight into developmental perturbations in vivo. The strengths And limitations of the methods we use to study metabolism are reviewed with reference to species-specific fundamental biology and plasticity and we discuss what the future holds for metabolic studies and the unanswered questions that remain.(AU)
Assuntos
Animais , Feminino , Embrião de Mamíferos/metabolismo , Trifosfato de Adenosina , Implantação do EmbriãoRESUMO
The practice of fat feedinghas become common in the d airy industry in a number of countries. There are several ideas as to how dietary lipids could influence reproductive performance. Highly saturated triacylglycerols (TAG), like palm oil, can increase milk yield but may aggravate negative energy balance and consequently impair fertility when fed during the first weeks postpartum. However, priming the lipid oxidation in the liver by feeding saturated lipid sources during the dry period has recently been shown to be a potentially promising strategy to mitigate fat mobilization and liver accumulation postpartum. Furthermore, polyunsaturated free fatty acids (FFA), such as omega-3 fatty acids and conjugated linoleic acids are fed to reduce the de novo fatty acid synthesis in the udder and thus the milk TAG content, which may be of modest benefit for overall energy balance. Furthermore, omega-6 and-3 poly unsaturated FFA are reported to alter follicular growth, steroid synthesis and prost aglandin metabolism in the ovary and endometrium, respectively. Omega-6 FFA are believed to have proinflammatory and thus PGF2α-stimulating properties rendering them extra value as neutraceutical early postpartum, while omega-3 FFA can weaken this inflammatory potency, leading to a higher chance of survival of the embryo when supplemented during the periconceptual period. Unfortunately, research results rarely provide aconsensus in this perspective. The consequences of these fat feeding strategies on oocyte and embryo quality remain an intriguing issue for debate. Dietary lipid supplementation may alter the microenvironment of the growing and maturing oocyte, of the early and older embryo and thus may affect reproductive outcome. We recently reported that dietary induced hyperlipidemic conditions can be harmful for embryo development and metabolism. However, to date, research results remain somewhat conflicting most probably due to differences in fat sources used in diet, and duration of supplementation and in experimental set up.
Assuntos
Animais , Fígado/anatomia & histologia , Gorduras na Dieta/análise , Reprodução/fisiologia , Dieta , Lipídeos/análiseRESUMO
The practice of fat feedinghas become common in the d airy industry in a number of countries. There are several ideas as to how dietary lipids could influence reproductive performance. Highly saturated triacylglycerols (TAG), like palm oil, can increase milk yield but may aggravate negative energy balance and consequently impair fertility when fed during the first weeks postpartum. However, priming the lipid oxidation in the liver by feeding saturated lipid sources during the dry period has recently been shown to be a potentially promising strategy to mitigate fat mobilization and liver accumulation postpartum. Furthermore, polyunsaturated free fatty acids (FFA), such as omega-3 fatty acids and conjugated linoleic acids are fed to reduce the de novo fatty acid synthesis in the udder and thus the milk TAG content, which may be of modest benefit for overall energy balance. Furthermore, omega-6 and-3 poly unsaturated FFA are reported to alter follicular growth, steroid synthesis and prost aglandin metabolism in the ovary and endometrium, respectively. Omega-6 FFA are believed to have proinflammatory and thus PGF2α-stimulating properties rendering them extra value as neutraceutical early postpartum, while omega-3 FFA can weaken this inflammatory potency, leading to a higher chance of survival of the embryo when supplemented during the periconceptual period. Unfortunately, research results rarely provide aconsensus in this perspective. The consequences of these fat feeding strategies on oocyte and embryo quality remain an intriguing issue for debate. Dietary lipid supplementation may alter the microenvironment of the growing and maturing oocyte, of the early and older embryo and thus may affect reproductive outcome. We recently reported that dietary induced hyperlipidemic conditions can be harmful for embryo development and metabolism. However, to date, research results remain somewhat conflicting most probably due to differences in fat sources used in diet, and duration of supplementation and in experimental set up.(AU)