Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
U.S. Department of Agriculture, Agricultural Research Service, Beltsville Agricultural Research Center (BARC), Beltsville, MD 20705, USA.
Int J Mol Sci. 2024 Jul 19;25(14):7919. doi: 10.3390/ijms25147919.
Mammalian spermatozoa rely on glycolysis and mitochondrial oxidative phosphorylation for energy leading up to fertilization. Sperm capacitation involves a series of well-regulated biochemical steps that are necessary to give spermatozoa the ability to fertilize the oocyte. Additionally, zinc ion (Zn) fluxes have recently been shown to occur during mammalian sperm capacitation. Semen from seven commercial boars was collected and analyzed using image-based flow cytometry before, after, and with the inclusion of 2 mM Zn containing in vitro capacitation (IVC) media. Metabolites were extracted and analyzed via Gas Chromatography-Mass Spectrometry (GC-MS), identifying 175 metabolites, with 79 differentially abundant across treatments ( < 0.05). Non-capacitated samples showed high levels of respiration-associated metabolites including glucose, fructose, citric acid, and pyruvic acid. After 4 h IVC, these metabolites significantly decreased, while phosphate, lactic acid, and glucitol increased ( < 0.05). With zinc inclusion, we observed an increase in metabolites such as lactic acid, glucitol, glucose, fructose, myo-inositol, citric acid, and succinic acid, while saturated fatty acids including palmitic, dodecanoic, and myristic acid decreased compared to 4 h IVC, indicating regulatory shifts in metabolic pathways and fatty acid composition during capacitation. These findings underscore the importance of metabolic changes in improving artificial insemination and fertility treatments in livestock and humans.
哺乳动物精子在受精前依赖糖酵解和线粒体氧化磷酸化来提供能量。精子获能涉及一系列受到严格调控的生化步骤，这些步骤对于赋予精子受精卵子的能力是必要的。此外，最近已经表明锌离子（Zn）通量在哺乳动物精子获能过程中发生。收集了来自七头商业公猪的精液，并在体外获能（IVC）前、后以及包含 2mM Zn 的 IVC 培养基中使用基于图像的流式细胞术进行分析。通过气相色谱-质谱法（GC-MS）提取和分析代谢物，共鉴定出 175 种代谢物，其中 79 种在不同处理组之间差异丰富（<0.05）。未获能的样本显示高水平的与呼吸相关的代谢物，包括葡萄糖、果糖、柠檬酸和丙酮酸。在 4 小时 IVC 后，这些代谢物显著减少，而磷酸盐、乳酸和葡糖醇增加（<0.05）。加入锌后，我们观察到乳酸、葡糖醇、葡萄糖、果糖、肌醇、柠檬酸和琥珀酸等代谢物增加，而棕榈酸、十二烷酸和肉豆蔻酸等饱和脂肪酸与 4 小时 IVC 相比减少，表明在获能过程中代谢途径和脂肪酸组成发生了调节变化。这些发现强调了代谢变化在改善家畜和人类人工授精和生育治疗中的重要性。
