Lei Tao, Guo Na, Liu Jie-Qiong, Tan Mei-Hua, Li Yu-Feng
Department of Reproductive Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China.
Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China.
Int J Clin Exp Pathol. 2014 Feb 15;7(3):1159-65. eCollection 2014.
In the assisted reproductive technique, cryopreserving in vitro-matured oocytes is a new strategy to extend the pool of total oocytes. However, oocyte cryopreservation technique is still unsatisfied. So the assessment of cyro-damage on meiotic spindle and mitochondrial function is necessary to evaluate and refine the current protocols.
The immature oocytes were donated from women undergoing ICSI cycles. Cytoskeleton was assessed by α-tubulin and mitochondria through the fluorescent ΔΨm reporter JC-1.
Relative inner membrane potential in MII oocytes from vIVM group sharply decreased, compared with the control (n=30) (1.397 vs. 1.019, P<0.05). 45.2% defective spindles were observed in fIVM group, compared with 48.0% in vIVM group (P>0.05). Oocytes in fIVM (35.5%, 11/31) and vIVM (40.0%, 10/25) displayed abnormal chromosome (P>0.05).
In vitro maturation (IVM) has an adverse effect on the organization of spindle and chromosome, and no significantly effect on spindle and chromosome was discovered after vitrification-thaw cycle, while there was obvious damage of oocyte mitochondrial function of in vitro-matured oocyte detected after warming, which may be the reason of the low following developmental potential.
在辅助生殖技术中，冷冻保存体外成熟卵母细胞是扩大总卵母细胞库的一种新策略。然而，卵母细胞冷冻保存技术仍不尽人意。因此，评估冷冻对减数分裂纺锤体和线粒体功能的损伤对于评估和完善当前方案是必要的。
未成熟卵母细胞来自接受ICSI周期的女性。通过α-微管蛋白评估细胞骨架，通过荧光ΔΨm报告基因JC-1评估线粒体。
与对照组（n = 30）相比，vIVM组MII期卵母细胞的相对内膜电位急剧下降（1.397对1.019，P < 0.05）。fIVM组观察到45.2%的纺锤体缺陷，vIVM组为48.0%（P > 0.05）。fIVM组（35.5%，11/31）和vIVM组（40.0%，10/25）的卵母细胞显示染色体异常（P > 0.05）。
体外成熟（IVM）对纺锤体和染色体的组织有不利影响，玻璃化冷冻-解冻周期后未发现对纺锤体和染色体有显著影响，而解冻后检测到体外成熟卵母细胞的卵母细胞线粒体功能有明显损伤，这可能是后续发育潜力低的原因。
