Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Switzerland.
Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Switzerland.
Cryobiology. 2019 Dec;91:40-52. doi: 10.1016/j.cryobiol.2019.10.200. Epub 2019 Oct 31.
The aim of this study was to investigate the effects of different concentrations of catalase in a TRIS-egg yolk extender on sperm quality and embryonic development after in vitro fertilization of frozen-thawed bull sperm. For this purpose, from each of 7 bulls 2 ejaculates were collected and diluted with a TRIS-egg yolk extender containing 0, 5, 10, 15 or 20 IU catalase/mL. Sperm quality was evaluated 0, 3, 6, 12 and 24 h after thawing by using computer assisted analysis of motility and by flow cytometric assays. Embryonic development was determined after in vitro fertilization of bovine oocytes. Semen diluted with TRIS-egg yolk extender containing different concentrations of catalase showed more motile sperm, more sperm with intact plasma membranes, acrosomes and DNA, a high mitochondrial membrane potential, a high esterase activity, a low calcium level, a lower amount of synthesis of reactive oxygen species and lower degree of lipid peroxidation of sperm compared to semen frozen without catalase (P < 0.05), but not before 3 h after thawing. There was a dose-response relationship with the most prominent effect of 20 IU catalase/mL. However, the improvement of sperm quality had no effect (P ≥ 0.05) on embryonic development after in vitro fertilization with 20 IU catalase/mL. In conclusion, the addition of catalase to the sperm extender improved sperm quality with no obvious effect on in vitro fertility.
本研究旨在探讨不同浓度的过氧化氢酶在 TRIS-卵黄稀释液中对冷冻解冻公牛精子体外受精后精子质量和胚胎发育的影响。为此，从 7 头公牛中采集了 2 份精液，并分别用含有 0、5、10、15 或 20IU 过氧化氢酶/ml 的 TRIS-卵黄稀释液进行稀释。在解冻后 0、3、6、12 和 24 小时，通过计算机辅助分析运动和流式细胞术检测评估精子质量。通过体外受精牛卵母细胞后确定胚胎发育情况。与未添加过氧化氢酶的冷冻精液相比，添加不同浓度过氧化氢酶的 TRIS-卵黄稀释液稀释的精液显示出更多的运动精子、更多的质膜完整、顶体和 DNA 完整的精子、较高的线粒体膜电位、较高的酯酶活性、较低的钙水平、较低的活性氧合成量和较低的精子脂质过氧化程度（P < 0.05），但在解冻后 3 小时内没有这种效果。随着 20IU 过氧化氢酶/ml 的剂量增加，效果最为显著。然而，添加 20IU 过氧化氢酶/ml 对体外受精后胚胎发育没有明显影响（P≥0.05）。总之，在精子稀释液中添加过氧化氢酶可提高精子质量，但对体外受精的受精能力没有明显影响。
