Department of Embryology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran.
Department of Cell Engineering, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.
Cryobiology. 2019 Feb;86:65-70. doi: 10.1016/j.cryobiol.2018.12.003. Epub 2018 Dec 8.
Application of an appropriate freezing carrier is crucial for improving post-thaw recovery of oligozoospermic samples. In this study, our purpose is developing a user-friendly, easy handling and close micro-quantity (MQ) straw along with different freezing media, for cryopreservation of oligozoospermic samples. Twenty oligozoospermic semen samples were collected and mixed with glycerol egg yolk citrate (GEYC) or Spermfreeze (SPF) medium. The mixture was loaded into MQ straws, sealed and stored in liquid nitrogen (LN) vapor. After freezing, the straws were transferred into cryotube and plunged into LN. Post-thawed sperm parameters including motion characteristics, viability, membrane and DNA integrity were evaluated one and three months after cryopreservation. The post-thawed sperm parameters were significantly reduced in GEYC and SPF medium compared to fresh samples. No statistically significant differences were seen in sperm characteristics between the two storage times (i.e. month 1 vs. month 3). Furthermore, GEYC medium yielded higher motility, viability and membrane integrity compared to SPF at both storage time-points. Sperm DNA integrity was also improved in GEYC group compared to SPF after 1 month of storage. The findings of our study showed that application of MQ straw along with GEYC, as the cryoprotectant, was beneficial for cryopreservation of low count semen samples.
应用适当的冷冻载体对于提高少精子症样本的解冻后恢复至关重要。本研究旨在开发一种用户友好、易于操作且微量（MQ）的 straw，以及不同的冷冻介质，用于冷冻少精子症样本。收集了 20 份少精子症精液样本，并与甘油蛋黄柠檬酸（GEYC）或 Spermfreeze（SPF）介质混合。将混合物装入 MQ straw 中，密封后存放在液氮（LN）蒸气中。冷冻后，将 straw 转移到 cryotube 中并浸入 LN 中。在冷冻保存 1 个月和 3 个月后，评估解冻后精子的运动特性、活力、膜和 DNA 完整性等参数。与新鲜样本相比，GEYC 和 SPF 介质中的解冻后精子参数显著降低。在两个储存时间（即 1 个月与 3 个月）之间，精子特性没有统计学上的显著差异。此外，在两个储存时间点，GEYC 介质均比 SPF 产生更高的运动能力、活力和膜完整性。与 SPF 相比，在储存 1 个月后，GEYC 组的精子 DNA 完整性也得到了改善。本研究结果表明，应用 MQ straw 与 GEYC 作为冷冻保护剂，有利于冷冻低计数精液样本。
