Zhu Kuanfeng, Song Yukun, He Zhi, Wang Peng, Wang Xuguang, Liu Guoshi
College of Animal Science, Xinjiang Agricultural University, Urumqi 830091, China.
Beijing Jingwa Agricultural Science & Technology Innovation Center, Beijing 101205, China.
Animals (Basel). 2024 Dec 18;14(24):3656. doi: 10.3390/ani14243656.
Seminal plasma is an important component of semen and has a significant effect on sperm function. However, the relationship between seminal plasma and sperm freezing capacity has not been fully studied.
Exploring metabolites and proteins related to the boar sperm freezing capacity in seminal plasma, by metabolomic and proteomic approaches, and directly verifying the protective effect of seminal plasma on the cryopreservation of boar sperm using high and low freezability seminal plasma as base freezing extender.
Semen samples were collected from 30 different boars, 11 high and 11 low freezing-resistant boars were selected after freezing 2~4 times, and seminal plasma was selected at the same time. Sperm motility and movement parameters were analyzed using a CASA system. Reproductive hormones (Testosterone, progesterone, estradiol, prolactin, prostaglandin F2α, luteinoid hormone) in seminal plasma were detected by ELISA. Analysis of proteins and metabolites in high and low freezing-resistant seminal plasma by proteomics and metabolomics techniques.
The six reproductive hormones tested were not significantly associated with sperm freezing resistance. A total of 13 differentially expressed metabolites (DEMs) and 38 differentially expressed proteins (DEPs) were identified, while a total of 348 metabolites and 1000 proteins were identified. These DEMs were related to energy metabolism, drugs, or environmental pollutants, while the DEPs were mainly involved in the cytoskeletal dynamics and cell adhesion processes. There were 33 metabolites and 70 proteins significantly associated with mean progress motility (PM) at 10 min and 2 h after thawing. The 70 related proteins were associated with cell division and cycle regulation in gene ontology (GO) terms, as well as KEGG pathways, thermogeneration, and pyruvate metabolism. Using highly freezable boar SP as a base freezing extender made no difference from using lowly freezable boar SP, and both were not as good as the commercial control.
There were significant differences in seminal plasma with different freezability, but the similarity was much greater than the difference. The protection effect of seminal plasma is not remarkable, and it does not exhibit superior cryoprotective properties compared to commercial semen cryoelongators.
This study provides a deeper understanding of how seminal plasma composition affects sperm freezabilty. It provides potential biomarkers and targets for improving sperm cryopreservation techniques.
精浆是精液的重要组成部分，对精子功能有显著影响。然而，精浆与精子冷冻能力之间的关系尚未得到充分研究。
通过代谢组学和蛋白质组学方法，探索精浆中与公猪精子冷冻能力相关的代谢物和蛋白质，并以高、低冷冻能力的精浆作为基础冷冻稀释液，直接验证精浆对公猪精子冷冻保存的保护作用。
从30头不同公猪采集精液样本，经2至4次冷冻后，挑选出11头高抗冻性和11头低抗冻性的公猪，并同时采集精浆。使用计算机辅助精子分析（CASA）系统分析精子活力和运动参数。通过酶联免疫吸附测定（ELISA）检测精浆中的生殖激素（睾酮、孕酮、雌二醇、催乳素、前列腺素F2α、促黄体生成素）。采用蛋白质组学和代谢组学技术分析高、低抗冻性精浆中的蛋白质和代谢物。
所检测的六种生殖激素与精子抗冻性无显著关联。共鉴定出13种差异表达代谢物（DEM）和38种差异表达蛋白质（DEP），同时共鉴定出348种代谢物和1000种蛋白质。这些DEM与能量代谢、药物或环境污染物有关，而DEP主要参与细胞骨架动力学和细胞黏附过程。有33种代谢物和70种蛋白质与解冻后10分钟和2小时的平均前进运动速度（PM）显著相关。这70种相关蛋白质在基因本体（GO）术语以及京都基因与基因组百科全书（KEGG）通路、产热和丙酮酸代谢方面与细胞分裂和周期调控相关。使用高冷冻能力的公猪精浆作为基础冷冻稀释液与使用低冷冻能力的公猪精浆没有差异，且两者均不如商业对照。
不同冷冻能力的精浆存在显著差异，但相似性远大于差异。精浆的保护作用不显著，与商业精液冷冻稀释液相比，未表现出优越的冷冻保护特性。
本研究更深入地了解了精浆成分如何影响精子冷冻能力。它为改进精子冷冻保存技术提供了潜在的生物标志物和靶点。
