State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, Institutes of Biomedical Sciences, School of Life Sciences, Inner Mongolia University, Hohhot, Inner Mongolia, People's Republic of China.
Department of Obstetrics and Gynecology, Reproductive Medicine Center, Inner Mongolia Baogang Hospital, Baotou, Inner Mongolia, People's Republic of China.
PLoS One. 2024 Apr 1;19(4):e0300538. doi: 10.1371/journal.pone.0300538. eCollection 2024.
The cryopreservation process damages oocytes and impairs development potential. As a potent antioxidant, C-phycocyanin (PC) regulates reproductive performance. However, its beneficial effects on vitrified human oocytes remain unknown.
In this study, human GV-stage oocytes obtained from controlled ovarian hyperstimulation (COH) cycles were randomly allocated to three groups: fresh oocyte without freezing (F group), vitrification in medium supplemented with PC (P group), and vitrification in medium without PC as control group (C group). After warming, viable oocytes underwent in vitro maturation.
Our results showed that 3 μg/mL PC treatment increased the oocyte maturation rate after cryopreservation. We also found that PC treatment maintains the regular morphological features of oocytes. After PC treatment, confocal fluorescence staining showed a significant increase in the mitochondrial membrane potential of the vitrified oocytes, along with a notable decrease in intracellular reactive oxygen species and the early apoptosis rate. Finally, after in vitro maturation and parthenogenetic activation, vitrified oocytes had a higher potential for cleavage and blastocyst formation after PC treatment.
Our results suggest that PC improves the developmental potential of cryopreserved human GV-stage oocytes by attenuating oxidative stress and early apoptosis and increasing the mitochondrial membrane potential.
冷冻过程会损害卵子并降低其发育潜能。C-藻蓝蛋白(PC)作为一种有效的抗氧化剂,可调节生殖性能。然而,其对玻璃化冷冻人卵的有益作用尚不清楚。
本研究中,将来自控制性卵巢超刺激(COH)周期的人类GV 期卵母细胞随机分为三组:未经冷冻的新鲜卵母细胞(F 组)、添加 PC 的培养基中玻璃化冷冻的卵母细胞(P 组)和不含 PC 的培养基中玻璃化冷冻的卵母细胞作为对照组(C 组)。解冻后,活卵母细胞进行体外成熟。
我们的结果表明,3μg/ml PC 处理可提高冷冻后卵母细胞的成熟率。我们还发现 PC 处理可保持卵母细胞的正常形态特征。经过 PC 处理后,共聚焦荧光染色显示玻璃化卵母细胞的线粒体膜电位显著增加,同时细胞内活性氧和早期凋亡率明显降低。最后,经过体外成熟和孤雌激活后,经 PC 处理的玻璃化卵母细胞在卵裂和囊胚形成方面具有更高的潜能。
我们的结果表明,PC 通过减轻氧化应激和早期凋亡,增加线粒体膜电位,改善了冷冻保存的人类 GV 期卵母细胞的发育潜能。