Division of Reproduction and Early Development, Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, UK.
Center for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, UK.
Biol Reprod. 2017 Jan 1;97(6):798-809. doi: 10.1093/biolre/iox135.
Approximately 65-75 days postpartum (dpp), the estrous cycles of nonlactating (dried off immediately postpartum: n = 12) and lactating (n = 13) Holstein Friesian cows were synchronized and on day 7 a single blastocyst derived from superovulated nulliparous Holstein Friesian heifers was transferred to each cow. A control group of nulliparous heifers (n = 8) were synchronized, inseminated to a standing heat, and slaughtered on the same day as nonlactating and lactating recipients (day 19; estrus = day 0). The uterine horn ipsilateral to the corpus luteum was flushed with 10 ml phosphate-buffered saline and the conceptus, and uterine luminal fluid (ULF) was snap-frozen in liquid nitrogen. Gene expression analysis of the conceptus was performed by RNA sequencing, while amino acid composition of ULF was determined by high-performance liquid chromatography. No differentially expressed genes (DEGs) were observed between conceptuses recovered from nonlactating and lactating cows. Eight DEGs were identified between conceptuses recovered from nonlactating cows and heifers. A total of 269 DEGs (100 up- and 169 downregulated) were identified between conceptuses recovered from lactating cows compared to heifers. Alanine, glycine, serine, threonine, arginine, leucine, and valine were significantly lower in abundance in ULF recovered from heifers compared to nonlactating or lactating cows. This study demonstrates that the environment in which the embryo develops post the blastocyst stage can have an effect on the conceptus transcriptome and amino acid composition of the ULF but this was mainly observed between the two extreme groups in terms of metabolic status (nulliparous heifers vs postpartum lactating cows).
大约在产后 65-75 天（dpp），非哺乳期（产后立即断奶：n=12）和哺乳期（n=13）荷斯坦弗里生奶牛的发情周期被同步，在第 7 天，将一个从超数排卵的初产荷斯坦弗里生小母牛获得的单个囊胚转移到每头奶牛中。一组初产小母牛（n=8）作为对照组进行同步发情，配种至静立发情，并在与非哺乳期和哺乳期受体相同的日子（第 19 天；发情=第 0 天）进行屠宰。用 10ml 磷酸盐缓冲盐水冲洗黄体同侧的子宫角，将胚胎和子宫腔液（ULF）迅速冷冻在液氮中。通过 RNA 测序对胚胎的基因表达进行分析，同时通过高效液相色谱法测定 ULF 的氨基酸组成。从非哺乳期和哺乳期奶牛中回收的胚胎之间没有观察到差异表达基因（DEGs）。从非哺乳期奶牛和小母牛中回收的胚胎之间鉴定出 8 个 DEG。与小母牛相比，从哺乳期奶牛中回收的胚胎中总共鉴定出 269 个 DEG（100 个上调和 169 个下调）。与非哺乳期或哺乳期奶牛相比，从小母牛中回收的 ULF 中丙氨酸、甘氨酸、丝氨酸、苏氨酸、精氨酸、亮氨酸和缬氨酸的丰度显著降低。这项研究表明，囊胚阶段后胚胎发育的环境会对胚胎转录组和 ULF 的氨基酸组成产生影响，但这主要在代谢状态（初产小母牛与产后哺乳期奶牛）两个极端群体之间观察到。
