公猪精液质量与精子脂质成分相关性研究

Correlation Study Between Semen Quality and Sperm Lipid Composition in Boars

【目的】建立公猪精液品质与精子脂质成分之间的相关性,为公猪精液品质准确评价提供支撑。【方法】本研究采集了大白和长白等代表性品种公猪的精液,使用计算机辅助精子分析(computer-assisted sperm analysis,CASA)系统对精子密度、精子活力、精子畸形率和精液体积等精液品质指标进行检测。根据精子活力将精液样品分为正常活力(≥70%,n=11)和低活力(<70%,n=11)两组,利用UPLC-Q-Exactive-Orbitrap/MS对两组精子样品进行非靶向脂质组分析。采用t检验(t tests)、偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)和相关性分析(correlation)等统计分析方法对脂质组学检测结果进行多元化分析。根据对分类具有重要贡献的变量(variable important in projection,VIP)值>1和错误发现率(false discovery rate,FDR)<0.05的双重标准进行筛选,得到两组精子样品之间差异脂质分子。【结果】正离子和负离子模式下共鉴别出166种差异脂质分子,其中70种差异脂质分子集中在磷脂酰胆碱(phosphatidylcholine,PC)这类脂质上。甘油二酯(diglyceride,DG)、鞘磷脂(sphingomyelin,SM)、PC、酵母甾醇(zymosterol ester,ZyE)和糖基神经酰胺(simple Glc series,Hex3Cer)等脂质亚类的含量在活力低的精子中显著减少,且均与精子活力呈显著正相关(P<0.05)。甘油三酯(triglyceride,TG)和磷脂酰胆碱酯(phosphatidylcholine ester,PC(e))在活力低的精子中显著增加,与精子活力呈显著负相关(P<0.05)。【结论】脂质组学可以准确区分不同活力精子中脂质亚类和脂质分子的组成差异,PC、DG、SM、PC、ZyE、Hex3Cer,TG和PC(e)等脂质的组成成分及其含量可作为区分精子活力高低的标志。

【Objective】The purpose of this experiment was to establish the correlation between boar semen quality and sperm lipid composition,providing support for accurate evaluation of boar semen quality.【Method】In this study,semen samples were collected from representative breeds of boars,such as Yorkshire pigs and Landrace pigs.The computer-assisted sperm analysis(CASA)system was used to measure semen quality parameters,including sperm density,sperm motility,sperm abnormality rate,and semen volume.The semen samples were classified as two groups based on sperm motility,including normal motility(≥70%,n=11)and low motility(<70%,n=11).Unbiased lipidomics analysis of the two groups of sperm samples was performed using UPLC-Q-Exactive-Orbitrap/MS multivariate statistical analysis methods,including t tests,partial least squares discriminant analysis(PLS-DA),and correlation analysis,were used to analyze the data of lipidomics.The difference of lipid molecules between the two groups was obtained according to VIP>1 and P<0.05.【Result】A total of 166 differential lipid molecules identified in both positive and negative ion modes,which mainly concentrated in phosphatidylcholine(PC).Lipid molecular species,including diglyceride(DG),sphingomyelin(SM),PC,Zymosterol Ester(ZyE),and simple Glc series(Hex3Cer),showed significant decrease in low motility sperm and were significantly positively correlated with sperm motility(P<0.05).Triglyceride(TG)and phosphatidylcholine ester(PC(e))showed significant increase in low motility sperm and were significantly negatively correlated with sperm motility(P<0.05).【Conclusion】Lipidomics could accurately distinguish the differences in lipid subpopulations and lipid molecular composition among different motile sperm.The composition and content of lipids such as PC,DG,SM,PC,ZyE,Hex3Cer,TG,and PC(e)could be used as markers to distinguish sperm motility.