Afedi P A, Larimore E L, Cushman R A, Raynie D, Perry G A
Department of Chemistry and Biochemistry, South Dakota State University, Brookings, SD, USA.
Department of Animal Science, South Dakota State University, Brookings, SD, USA.
Domest Anim Endocrinol. 2021 Jul;76:106606. doi: 10.1016/j.domaniend.2021.106606. Epub 2021 Mar 2.
Bovine follicular fluid (FF) creates a unique microenvironment in follicles necessary for follicle growth, oocyte maturation, and estradiol (E2) production. The objective of this study was to analyze changes in proteins in FF and plasma (PL) from animals with high E2 (HE2) or low E2 (LE2) during the preovulatory period. Beef cows were synchronized, and follicular dynamics and ovulatory response were monitored using transrectal ultrasonography. Nine cows were selected and slaughtered, blood samples were collected at slaughter and FF was aspirated from dominant follicles (DF; >10 mm). Abundant proteins (albumin, IgG, IgA, and alpha-1-antitrypsin) were depleted from both PL and FF. Peptides were labeled with iTRAQ reagents and quantified using 2-dimentional liquid chromatography ESI-based mass spectrometry. Estradiol was associated with protein changes in PL and FF. Protein expression changes between FF HE2 and FF LE2 were greater than between PL HE2 and PL LE2. There were 15 up-regulated proteins and 10 down-regulated proteins in FF HE2 compared to FF LE2, and 7 proteins up-regulated and 9 proteins down-regulated in PL HE2 compared to PL LE2. Several of the differentially expressed proteins function in follicle development and were mainly categorized under cellular process and metabolic process. Pathway analysis identified the up- and down-regulated proteins were predominantly associated with the complement and coagulation cascades. The data demonstrate E2 regulates a wide range of reproductive associated proteins in bovine PL and FF and can provide the basis for further investigation of specific processes involved in such regulation.
牛卵泡液（FF）在卵泡内营造了一个独特的微环境，这对卵泡生长、卵母细胞成熟以及雌二醇（E2）的产生而言必不可少。本研究的目的是分析处于排卵前期的高E2（HE2）或低E2（LE2）动物的卵泡液和血浆（PL）中蛋白质的变化。对肉牛进行同期发情处理，并通过直肠超声监测卵泡动态和排卵反应。挑选9头母牛并屠宰，屠宰时采集血样，从优势卵泡（DF；>10 mm）中抽吸卵泡液。血浆和卵泡液中的丰富蛋白质（白蛋白、IgG、IgA和α-1抗胰蛋白酶）均有所减少。用iTRAQ试剂标记肽段，并使用基于二维液相色谱电喷雾电离的质谱进行定量分析。雌二醇与血浆和卵泡液中的蛋白质变化有关。卵泡液HE2组和卵泡液LE2组之间的蛋白质表达变化大于血浆HE2组和血浆LE2组之间的变化。与卵泡液LE2组相比，卵泡液HE2组中有15种上调蛋白和10种下调蛋白；与血浆LE2组相比，血浆HE2组中有7种上调蛋白和9种下调蛋白。几种差异表达的蛋白质在卵泡发育中发挥作用，主要归类于细胞过程和代谢过程。通路分析表明，上调和下调的蛋白质主要与补体和凝血级联反应有关。这些数据表明，E2可调节牛血浆和卵泡液中多种与生殖相关的蛋白质，可为进一步研究这种调节所涉及的具体过程提供依据。
