Centre of Excellence in Clinical Embryology, Department of Reproductive Science, Kasturba Medical College, Manipal Academy of Higher Education, Manipal 576104, India.
Division of Reproductive Genetics, Department of Reproductive Science, Kasturba Medical College, Manipal Academy of Higher Education, Manipal 576104, India.
Cells. 2024 May 30;13(11):954. doi: 10.3390/cells13110954.
Reduced oxygen during embryo culture in human ART prevents embryo oxidative stress. Oxidative stress is also the major mechanism by which maternal diabetes impairs embryonic development. This study employed induced hyperglycemia prepubertal mice to mimic childhood diabetes to understand the effects of varying oxygen tension during in vitro embryonic development. The oocytes were fertilized and cultured at low (≈5%) oxygen (LOT) or atmospheric (≈20%) oxygen tension (HOT) for up to 96 h. Embryo development, apoptosis in blastocysts, inner cell mass (ICM) outgrowth proliferation, and expression were assessed. Though the oocyte quality and meiotic spindle were not affected, the fertilization rate (94.86 ± 1.18 vs. 85.17 ± 2.81), blastocyst rate (80.92 ± 2.92 vs. 69.32 ± 2.54), and ICM proliferation ability (51.04 ± 9.22 vs. 17.08 ± 3.05) of the hyperglycemic embryos were significantly higher in the LOT compared to the HOT group. On the other hand, blastocysts from the hyperglycemic group, cultured at HOT, had a 1.5-fold increase in apoptotic cells compared to the control and lower transcripts in ICM outgrowths compared to the LOT. Increased susceptibility of embryos from hyperglycemic mice to higher oxygen tension warrants the need to individualize the conditions for embryo culture systems in ART clinics, particularly when an endogenous maternal pathology affects the ovarian environment.
胚胎培养过程中降低氧气可防止胚胎氧化应激。氧化应激也是母体糖尿病损害胚胎发育的主要机制。本研究采用诱导性青春期前高血糖小鼠模拟儿童糖尿病，以了解体外胚胎发育过程中不同氧张力的影响。卵母细胞在低氧（≈5%）（LOT）或常氧（≈20%）（HOT）条件下受精和培养长达 96 小时。评估胚胎发育、囊胚凋亡、内细胞团（ICM）外胚层增殖和 表达。尽管卵母细胞质量和减数分裂纺锤体不受影响，但受精率（94.86 ± 1.18 比 85.17 ± 2.81）、囊胚率（80.92 ± 2.92 比 69.32 ± 2.54）和 ICM 增殖能力（51.04 ± 9.22 比 17.08 ± 3.05）在 LOT 组均显著高于 HOT 组。另一方面，与对照组相比，来自高血糖组的在 HOT 下培养的囊胚凋亡细胞增加了 1.5 倍，而与 LOT 相比，ICM 外胚层中的 转录物减少。高血糖小鼠胚胎对高氧张力的敏感性增加，这使得有必要根据 ART 诊所中胚胎培养系统的具体情况进行个体化处理，特别是当内源性母体病理影响卵巢环境时。
