Fatty acid uptake and accumulation in lipid droplets are essential processes of lipid metabolism. Oocyte in vitro culture in media enriched with fatty acid is used to modify the lipid content and composition, aiming to study the consequences of obesity and enhance cell cryotolerance. We applied Raman spectroscopy and deuterium labeling approach to quantify stearic acid uptake and investigate its incorporation within oocytes. Our data suggest that deuterium labeling does not affect oocyte maturation rates. The efficiency of deuterated stearic acid (dSA) uptake was shown to decrease with the increase of its concentration in culture medium and the duration of in vitro culture. The molar ratio between dSA and bovine serum albumin has no significant effect on the dSA uptake for 200 μM but modifies concentration dependence of the lipid uptake. dSA accumulates in all the lipid droplets inside oocytes. Different lipid droplets within the same oocyte exhibit different concentrations of dSA. The scatter in the dSA concentration in lipid droplets decreases with the culture time. Using dSA as an example, we provide a comprehensive description of how fatty acid concentration, its molar ratio versus bovine serum albumin, and culture time affect the uptake of the fatty acids in oocytes. Raman microspectroscopy of deuterium-labeled fatty acids is a nondestructive tool providing information about fatty acid uptake and heterogeneity of their accumulation between lipid droplets within the single oocyte.

脂肪酸在脂滴中的吸收和积累是脂质代谢的基本过程。卵母细胞在富含脂肪酸的培养基中的体外培养可用于修饰脂质含量和组成，旨在研究肥胖症的后果并增强细胞的耐低温性。我们应用拉曼光谱和氘标记方法来量化硬脂酸的摄取并研究其在卵母细胞中的掺入。我们的数据表明氘标记不影响卵母细胞成熟率。氘化硬脂酸（dSA）的吸收效率随着其在培养基中的浓度和体外持续时间的增加而降低文化。dSA和牛血清白蛋白之间的摩尔比对200μM的dSA摄取量没有明显影响，但会改变脂质摄取的浓度依赖性。dSA聚集在卵母细胞内的所有脂质小滴中。同一卵母细胞内的不同脂质滴表现出不同的dSA浓度。脂滴中dSA浓度的分散随培养时间而降低。以dSA为例，我们提供了脂肪酸浓度，其相对于牛血清白蛋白的摩尔比以及培养时间如何影响卵母细胞中脂肪酸摄取的全面描述。氘标记脂肪酸的拉曼光谱法是一种非破坏性工具，可提供有关卵母细胞内脂滴之间脂肪酸摄取及其堆积不均的信息。