Ge Hongshan, Tollner Theodore L, Hu Zhen, Da Mimi, Li Xiaohe, Guan HeQin, Shan Dan, Lu Jieqiang, Huang Changjiang, Dong Qiaoxiang
Reproductive Health Center, Second Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang Province, People's Republic of China.
Reprod Fertil Dev. 2012;24(7):945-52. doi: 10.1071/RD11212.
The present study was designed to determine whether controlled ovarian hyperstimulation (COH) and in vitro maturation (IVM), two common clinical procedures in human IVF treatment, have an impact on mitochondrial DNA (mtDNA) copy number and mitochondrial function in oocytes. Matured mouse oocytes recovered following COH, IVM and natural cycles (NC), which simulated those treatments in human clinic IVF treatment. The copies of mtDNA, the activity of mitochondria as determined by inner mitochondrial membrane potential and oocyte adenosine trisphosphate (ATP) content, pattern of mitochondrial distribution, reactive oxygen species (ROS) levels and the integrity of the cytoskeleton were evaluated in oocytes. Significant differences were detected between COH and NC groups in all measures, except the pattern of mitochondrial distribution and ROS levels. There were also significant differences detected between IVM and NC treatment groups in the copies of mitochondrial DNA, the level of ROS and the integrity of the cytoskeleton in oocytes. In conclusion, the results of this investigation indicate that non-physiological COH and IVM treatments inhibit mtDNA replication, alter mitochondrial function and increase the percentage of abnormal cytoskeleton and ROS production. Damage related to the mitochondria may partly explain the low efficiency of IVF and high rate of embryonic loss associated with these clinical procedures.
本研究旨在确定控制性卵巢过度刺激（COH）和体外成熟（IVM）这两种人类体外受精（IVF）治疗中的常见临床程序是否会对卵母细胞中的线粒体DNA（mtDNA）拷贝数和线粒体功能产生影响。在COH、IVM和自然周期（NC）后回收成熟的小鼠卵母细胞，这些周期模拟了人类临床IVF治疗中的那些处理。对卵母细胞中的mtDNA拷贝数、通过线粒体内膜电位测定的线粒体活性、卵母细胞三磷酸腺苷（ATP）含量、线粒体分布模式、活性氧（ROS）水平以及细胞骨架的完整性进行了评估。除了线粒体分布模式和ROS水平外，在所有测量指标上，COH组和NC组之间均检测到显著差异。在卵母细胞的线粒体DNA拷贝数、ROS水平和细胞骨架完整性方面，IVM组和NC治疗组之间也检测到显著差异。总之，本研究结果表明，非生理性的COH和IVM处理会抑制mtDNA复制、改变线粒体功能，并增加异常细胞骨架和ROS产生的百分比。与线粒体相关的损伤可能部分解释了与这些临床程序相关的IVF低效率和高胚胎丢失率。
