Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Prosp. Lavrent'eva 10, Novosibirsk, 630090, Russia.
Institute of Automation and Electrometry, Siberian Branch of the Russian Academy of Sciences, Prosp. Koptyuga 1, Novosibirsk, 630090, Russia.
Cryobiology. 2021 Apr;99:55-63. doi: 10.1016/j.cryobiol.2021.01.014. Epub 2021 Jan 21.
Lipids significantly affect embryo cryopreservation in some mammalian species depending on the cell lipidome quantity and composition. One of the ways to study the relationship between lipid content and cryotolerance of cells is to study the effect of lipidome modification on laboratory mice. The objective of this research was to study how in vitro culture of mouse embryos with linoleic acid (LA) will affect lipid phase transition (LPT) during cooling and subsequent embryo development after cryopreservation. Embryos obtained in vivo at the 2-cell stage were cultured with 200 μM LA for 46 h up to the morula/blastocyst stage. Thereafter, one portion of embryos was slowly frozen to reveal the effect of LA on survival after cryopreservation, another portion was used to characterize the lipid composition and to determine the temperature of the LPT onset. Confocal fluorescence microscopy of Nile Red stained embryos showed a significant increase in lipid content of the LA treated group compared to the controls. Raman measurements showed that the onset of LPT in LA treated embryos is lower than in untreated ones: -5 °C vs +2 °C. However, these changes in the LPT onset did not affect the survival rates of embryos after cryopreservation. In summary, in vitro culture with LA changes the biophysical characteristics of embryos' lipidome and is realized in lower LPT onset, but this does not affect embryo survival after cryopreservation.
脂质在某些哺乳动物物种的胚胎冷冻中具有显著影响，这取决于细胞脂类组的数量和组成。研究脂质含量与细胞抗冻性之间关系的方法之一是研究脂类组修饰对实验鼠的影响。本研究的目的是研究在体外培养含有亚油酸 (LA) 的小鼠胚胎将如何影响冷却过程中的脂质相转变 (LPT) 以及冷冻保存后胚胎的后续发育。在体内获得的 2 细胞期胚胎在含有 200μM LA 的条件下培养 46 小时，直至桑椹胚/囊胚阶段。此后，一部分胚胎被缓慢冷冻，以揭示 LA 对冷冻保存后存活的影响，另一部分用于表征脂质组成，并确定 LPT 起始温度。尼罗红染色胚胎的共焦荧光显微镜显示，与对照组相比，LA 处理组的脂质含量显著增加。拉曼测量显示，LA 处理胚胎的 LPT 起始温度低于未处理胚胎：-5°C 对 +2°C。然而，LPT 起始的这些变化并未影响冷冻保存后胚胎的存活率。总之，LA 的体外培养改变了胚胎脂类组的生物物理特性，并且在较低的 LPT 起始时实现，但这并不影响冷冻保存后胚胎的存活。
