Li Ming-Wen, Glass Olivia C, Zarrabi Jasmin, Baker Lisa N, Lloyd K C Kent
Mouse Biology Program, University of California, Davis, CA 95618, United States.
J Fertili In Vitro. 2016 May;4(2). doi: 10.4172/2375-4508.1000175. Epub 2016 Mar 18.
Different protocols incorporating methyl-β-cyclodextrin (MBCD) and reduced glutathione (GSH) have been reported to improve IVF recovery of cryopreserved mouse sperm on a C57BL/6 (J and N) genetic background. However, it is not clear which IVF protocol is most appropriate when using the various methods to cryorecover sperm with different sperm quality and sample volumes. Therefore, in the present study we correlated sperm motility with fertilization rate and compared the efficiency of different IVF methods using various sperm samples so as to establish general guidelines for mouse sperm cryorecovery by IVF. High linear correlation between sperm fertilization rate and progressive motility was found, R was 0.9623 and 0.9993 for pre-freezing and post-thaw progressive motility, respectively. High amounts of cryoprotective agent (CPA) were observed to impair both sperm capacitation and fertilization. Moreover, the presence of a large number of immotile sperm in the sperm-oocyte co-incubation drop was found to reduce IVF success which could be partially reversed by supplementation using monothioglycerol (MTG) during centrifugation. It was concluded that the efficiency of IVF using cryorecovered mouse sperm in media containing MBCD and GSH can be predicted from sperm progressive motility. High concentrations of CPA and immotile sperm should be mitigated prior to IVF. The optimum IVF method should be selected based on sperm sample volume and sperm parameters.
据报道，不同的包含甲基-β-环糊精（MBCD）和还原型谷胱甘肽（GSH）的方案可提高C57BL/6（J和N）遗传背景下冷冻保存的小鼠精子的体外受精回收率。然而，当使用各种方法对不同精子质量和样本体积的精子进行冷冻复苏时，尚不清楚哪种体外受精方案最合适。因此，在本研究中，我们将精子活力与受精率相关联，并比较了使用各种精子样本的不同体外受精方法的效率，以便建立通过体外受精进行小鼠精子冷冻复苏的一般指南。发现精子受精率与前向运动性之间存在高度线性相关性，冷冻前和解冻后的前向运动性的R分别为0.9623和0.9993。观察到大量的冷冻保护剂（CPA）会损害精子获能和受精。此外，发现在精子-卵母细胞共孵育滴中存在大量不活动精子会降低体外受精成功率，在离心过程中使用单硫甘油（MTG）补充可部分逆转这种情况。得出的结论是，在含有MBCD和GSH的培养基中使用冷冻复苏的小鼠精子进行体外受精的效率可以通过精子前向运动性来预测。在体外受精之前，应减轻高浓度的CPA和不活动精子的影响。应根据精子样本体积和精子参数选择最佳的体外受精方法。
