Department of Animal Sciences, University of Illinois Urbana-Champaign, IL 61801.
Ajinomoto Co. Inc., Tokyo, Japan 104.
J Dairy Sci. 2023 Sep;106(9):6567-6576. doi: 10.3168/jds.2022-22390. Epub 2023 Jul 31.
Rumen-protected Lys (RPL) fed to Holstein cows prepartum resulted in a greater intake and improved health of their calves during the first 6 wk of life. However, whether increased supply of Lys in late gestation can influence placental tissue and, if so, which pathways are affected remain to be investigated. Therefore, we hypothesize that feeding RPL during late gestation could modulate placental metabolism, allowing for improved passage of nutrients to the fetus and thus influencing the offspring development. Therefore, we aimed to determine the effects of feeding RPL (AjiPro-L Generation 3, Ajinomoto Health and Nutrition North America) prepartum (0.54% DM of TMR) on mRNA gene expression profiles of placental samples of Holstein cows. Seventy multiparous Holstein cows were randomly assigned to 1 of 2 dietary treatments, consisting of TMR top-dressed with RPL (PRE-L) or without (control, CON), fed from 27 ± 5 d prepartum until calving. After natural delivery (6.87 ± 3.32 h), placentas were rinsed with physiological saline (0.9% sodium chloride solution) to clean any dirtiness from the environment and weighed. Then, 3 placentomes were collected, one from each placental region (cranial, central, and caudal), combined and flash-frozen in liquid nitrogen to evaluate the expression of transcripts and proteins related to protein metabolism and inflammation. Placental weights did not differ from cows in PRE-L (15.5 ± 4.03 kg) and cows in CON (14.5 ± 4.03 kg). Feeding RPL prepartum downregulated the expression of NOS3 (nitric oxide synthase 3), involved in vasodilation processes, and SOD1, which encodes the enzyme superoxide dismutase, involved in oxidative stress processes. Additionally, feeding RPL prepartum upregulated the expression of transcripts involved in energy metabolism (SLC2A3, glucose transporter 3; and PCK1, phosphoenolpyruvate carboxykinase 1), placental metabolism and cell proliferation (FGF2, fibroblast growth factor 2; FGF2R, fibroblast growth factor 2 receptor; and PGF, placental growth factor), Met metabolism (MAT2A, methionine adenosyltransferase 2-α), and tended to upregulate IGF2R (insulin-like growth factor 2 receptor). Placental FGF2 and LRP1 (low-density lipoprotein receptor-related protein 1) protein abundance were greater for cows that received RPL prepartum than cows in CON. In conclusion, feeding RPL to prepartum dairy cows altered uteroplacental expression of genes and proteins involved in cell proliferation, and in metabolism and transport of glucose. Such changes are illustrated by increased expression of SLC2A3 and PCK1 and increased protein abundance of FGF2 and LRP1 in uteroplacental tissue of cows consuming RPL.
产前给荷斯坦奶牛饲喂包膜赖氨酸（RPL）可增加其产犊后前 6 周内小牛的采食量并改善其健康状况。然而，妊娠后期赖氨酸供应量的增加是否会影响胎盘组织，如果会，哪些途径会受到影响，仍有待研究。因此，我们假设在妊娠后期饲喂 RPL 可以调节胎盘代谢，从而改善营养物质向胎儿的传递，从而影响后代的发育。因此，我们旨在确定产前（TMR 的 0.54% DM）饲喂包膜赖氨酸（AjiPro-L Generation 3，Ajinomoto Health and Nutrition North America）对荷斯坦奶牛胎盘样本中 mRNA 基因表达谱的影响。70 头经产荷斯坦奶牛被随机分配到 2 种饮食处理中的 1 种，包括 TMR 上撒有 RPL（PRE-L）或没有 RPL（对照，CON），从产前 27±5 天开始饲喂至分娩。自然分娩（6.87±3.32 小时）后，用生理盐水（0.9%氯化钠溶液）冲洗胎盘以清除环境中的任何污垢并称重。然后，从每个胎盘区域（颅侧、中央和尾侧）收集 3 个胎盘，合并并在液氮中快速冷冻，以评估与蛋白质代谢和炎症相关的转录物和蛋白质的表达。产前饲喂 RPL 的奶牛的胎盘重量与 PRE-L 组（15.5±4.03kg）和 CON 组（14.5±4.03kg）的奶牛没有差异。产前饲喂 RPL 下调了参与血管扩张过程的 NOS3（一氧化氮合酶 3）和参与氧化应激过程的 SOD1（超氧化物歧化酶 1）的表达。此外，产前饲喂 RPL 上调了参与能量代谢（SLC2A3，葡萄糖转运蛋白 3；和 PCK1，磷酸烯醇丙酮酸羧激酶 1）、胎盘代谢和细胞增殖（FGF2，成纤维细胞生长因子 2；FGF2R，成纤维细胞生长因子 2 受体；和 PGF，胎盘生长因子）、Met 代谢（MAT2A，蛋氨酸腺苷转移酶 2-α）和 IGF2R（胰岛素样生长因子 2 受体）表达的转录物的表达。产前饲喂 RPL 的奶牛的胎盘 FGF2 和 LRP1（低密度脂蛋白受体相关蛋白 1）蛋白丰度高于 CON 组的奶牛。总之，产前给奶牛饲喂 RPL 改变了与细胞增殖以及葡萄糖代谢和转运相关的 uteroplacental 基因和蛋白质的表达。这种变化通过 SLC2A3 和 PCK1 的表达增加以及 FGF2 和 LRP1 的蛋白丰度增加在消耗 RPL 的奶牛的 uteroplacental 组织中得到体现。
