Energy metabolism disorders during in vitro maturation of bovine cumulus-oocyte complexes interfere with blastocyst quality and metabolism.

Glucose and fatty acids (FA) metabolism disturbances during oocyte in vitro maturation (IVM) affect their metabolism and surrounding cumulus cells, but only inhibition of glucose metabolism decreases embryo culture efficiency. Therefore, the present experiment aimed to reveal if glucose or FA metabolism inhibition leads to the disruption of embryo developmental potential, and to characterize the metabolic landscape of embryos reaching the blastocyst stage. Inhibitors of glucose (IO + DHEA) or FA (ETOMOXIR) metabolism were applied during IVM, and the control group was matured under standard conditions. Blastocysts obtained from experimental and control groups were analyzed with regard to lipidome and metabolome (mass spectrometry), transcriptome (RNA-Seq) and fluorescence lipid droplets staining (BODIPY). We showed that inhibition of glucose and fatty acid metabolism leads to cellular stress response compromising the quality of preimplantation embryos. The inhibition of energy metabolism affects membrane fluidity as well as downregulates fatty acids biosynthesis and gene expression of trophectoderm cell line markers. Therefore, we conclude that oocyte maturation environment exerts a substantial effect on preimplantation development programming at cellular and molecular levels.

Species and embryo genome origin affect lipid droplets in preimplantation embryos.

Mammalian embryo development is affected by multiple metabolism processes, among which energy metabolism seems to be crucial. Therefore the ability and the scale of lipids storage in different preimplantation stages might affect embryos quality. The aim of the present studies was to show a complex characterization of lipid droplets (LD) during subsequent embryo developmental stages. It was performed on two species (bovine and porcine) as well as on embryos with different embryo origin [after in vitro fertilization (IVF) and after parthenogenetic activation (PA)]. Embryos after IVF/PA were collected at precise time points of development at the following stages: zygote, 2-cell, 4-cell, 8/16-cell, morula, early blastocyst, expanded blastocyst. LD were stained with BODIPY 493/503 dye, embryos were visualized under a confocal microscope and images were analyzed with the ImageJ Fiji software. The following parameters were analyzed: lipid content, LD number, LD size and LD area within the total embryo. The most important results show that lipid parameters in the IVF vs. PA bovine embryos differ at the most crucial moments of embryonic development (zygote, 8-16-cell, blastocyst), indicating possible dysregulations of lipid metabolism in PA embryos. When bovine vs. porcine species are compared, we observe higher lipid content around EGA stage and lower lipid content at the blastocyst stage for bovine embryos, which indicates different demand for energy depending on the species. We conclude that lipid droplets parameters significantly differ among developmental stages and between species but also can be affected by the genome origin.

Response of Bovine Cumulus-Oocytes Complexes to Energy Pathway Inhibition during In Vitro Maturation.

Glucose or fatty acids (FAs) metabolisms may alter the ovarian follicle environment and thus determine oocyte and the nascent embryo quality. The aim of the experiment was to investigate the effect of selective inhibition of glucose (iodoacetate + DHEA) or FA (etomoxir) metabolism on in vitro maturation (IVM) of bovine COCs (cumulus-oocyte complexes) to investigate oocyte's development, quality, and energy metabolism. After in vitro fertilization, embryos were cultured to the blastocyst stage. Lipid droplets, metabolome, and lipidome were analyzed in oocytes and cumulus cells. mRNA expression of the selected genes was measured in the cumulus cells. ATP and glutathione relative levels were measured in oocytes. Changes in FA content in the maturation medium were evaluated by mass spectrometry. Our results indicate that only glucose metabolism is substantial to the oocyte during IVM since only glucose inhibition decreased embryo culture efficiency. The most noteworthy differences in the reaction to the applied inhibition systems were observed in cumulus cells. The upregulation of ketone body metabolism in the cumulus cells of the glucose inhibition group suggest possibly failed attempts of cells to switch into lipid consumption. On the contrary, etomoxir treatment of the oocytes did not affect embryo development, probably due to undisturbed metabolism in cumulus cells. Therefore, we suggest that the energy pathways analyzed in this experiment are not interchangeable alternatives in bovine COCs.

Energy metabolism of follicular environment during oocyte growth and maturation.

Oocyte quality is affected by many factors, among which the environment of growth and maturation seems to be crucial. Studies show that well balanced oocyte energy metabolism has a significant impact on several elements of cytoplasmic and nuclear maturation as well as further embryo developmental competence. Therefore homeostasis between metabolism of glucose and fatty acids in the oocyte is being widely described nowadays. This review aims to discuss the follicular (in vivo) or maturation media (in vitro) environments with regard to glucose and fatty acid metabolism, as the main sources of the energy for the oocyte. A great emphasis is given on the balance between those two metabolic pathways and its further impact on female fertility.

Nutrients Composition in Fit Snacks Made from Ostrich, Beef and Chicken Dried Meat.

The aim of the study was to compare three types of meat snacks made from ostrich, beef, and chicken meat in relation to their nutrients content including fat, fatty acids, heme iron, and peptides, like anserine and carnosine, from which human health may potentially benefit. Dry meat samples were produced, from one type of muscle, obtained from ostrich (m.ambiens), beef (m. semimembranosus), and broiler chicken meat (m. pectoralis major). The composition of dried ostrich, beef, and chicken meat, with and without spices was compared. We show that meat snacks made from ostrich, beef, and chicken meat were characterized by high concentration of nutrients including proteins, minerals (heme iron especially in ostrich, than in beef), biologically active peptides (carnosine-in beef, anserine-in ostrich then in chicken meat). The, beneficial to human health, n-3 fatty acids levels differed significantly between species. Moreover, ostrich jerky contained four times less fat as compared to beef and half of that in chicken. In conclusion we can say that dried ostrich, beef, and chicken meat could be a good source of nutritional components.

Hepatoprotective, Hypoglycemic, and Hypolipidemic Effect of Chokeberry Pomace on Polish Merino Lambs.

To properly understand the biological effect of polyphenol compounds, it should not be assumed that they are generally bioavailable and are reaching tissues as expected. It is important to fully understand how polyphenol compounds are absorbed, metabolized, and finally eliminated from the organism. Most polyphenol compounds occur in the forms that cannot be absorbed in their primary form. Sheep make compounds bioavailable due to their unique digestive system properties. Despite this, several species of ruminants likely to serve as an experimental model were considered. However, due to the high costs for cattle and low popularity in the region of goats, sheep were selected as the experimental model. In the study, 24 Polish Merino lambs were randomly divided into a control and two experimental groups. The experimental groups were administered diets with the addition of 150 or 300 g of chokeberry pomace per each kg of complete feed mixture. Phenolics present in the chokeberry pomace were found to modulate biochemical blood parameters, resulting in hypoglycemic and hypolipidemic effects. Finally, the increase in total phenolics in the serum and liver of lambs induced a health-promoting effect on liver metabolic profile parameters.

Chokeberry Pomace as a Determinant of Antioxidant Parameters Assayed in Blood and Liver Tissue of Polish Merino and Wrzosówka Lambs.

Despite being a plant by-product, chokeberry pomace is believed to exert some therapeutic effects because it is one of the richest sources of highly bioavailable non-enzymatic antioxidants. The aim of this study was to determine the functionality of bioactive compounds present in the Aronia melanocarpa pomace (chokeberry) based on enzymatic and non-enzymatic parameters related to the active defence of liver and blood against the effects of oxidative stress. The experiment was conducted with 48 lambs of two breeds-Polish Merino and Wrzosówka. Experimental groups were administered the basic feed with the addition of 150 g or 300 g of black chokeberry pomace per each kg of the complete feed. The activities of antioxidative enzymes (superoxide dismutase, glutathione peroxidase), peptides (glutathione, glutathione disulfide), and a lipid peroxidation indicator (malondialdehyde), as well as the capacity of non-enzymatic antioxidants were investigated. The results proved a strong effect of bioactive compounds contained in the black chokeberry pomace on the estimated parameters. The inclusion of chokeberry pomace in feed mixtures brought many benefits linked with the antioxidative protection. Parameters responsible for the oxidative status were significantly modified despite the commonly-held view about a limited possibility of transferring phenolic compounds to the organs.