Forde Niamh, Simintiras Constantine A, Sturmey Roger, Mamo Solomon, Kelly Alan K, Spencer Thomas E, Bazer Fuller W, Lonergan Pat
School of Agriculture and Food Science, University College Dublin, Dublin, Ireland.
Center for Cardiovascular and Metabolic Research, University of Hull, Hull, United Kingdom.
PLoS One. 2014 Jun 24;9(6):e100010. doi: 10.1371/journal.pone.0100010. eCollection 2014.
In cattle, conceptus-maternal interactions are critical for the establishment and maintenance of pregnancy. A major component of this early interaction involves the transport of nutrients and secretion of key molecules by uterine epithelial cells to help support conceptus development during the peri-implantation period of pregnancy. Objectives were to: 1) analyze temporal changes in the amino acid (AA) content of uterine luminal fluid (ULF) during the bovine estrous cycle; 2) understand conceptus-induced alterations in AA content; 3) determine expression of AA transporters in the endometrium and conceptus; and 4) determine how these transporters are modulated by (Progesterone) P4. Concentrations of aspartic acid, arginine, glutamine, histidine, lysine, isoleucine, leucine, phenylalanine and tyrosine decreased on Day 16 of the estrous cycle but increased on Day 19 in pregnant heifers (P<0.05). Glutamic acid only increased in pregnant heifers on Day 19 (P<0.001). Asparagine concentrations were greater in ULF of cyclic compared to pregnant heifers on Day 7 (P<0.05) while valine concentrations were higher in pregnant heifers on Day 16 (P<0.05). Temporal changes in expression of the cationic AA transporters SLC7A1 SLC7A4 and SLC7A6 occurred in the endometrium during the estrous cycle/early pregnancy coordinate with changes in conceptus expression of SLC7A4, SLC7A2 and SLC7A1 (P<0.05). Only one acidic AA transporter (SLC1A5) increased in the endometrium while conceptus expression of SLC1A4 increased (P<0.05). The neutral AA transporters SLC38A2 and SLC7A5 increased in the endometrium in a temporal manner while conceptus expression of SLC38A7, SLC43A2, SLC38A11 and SLC7A8 also increased (P<0.05). P4 modified the expression of SLC1A1, -1A4, -1A5, -38A2, -38A4, -38A7, -43A2, -6A14, -7A1, -7A5 and -7A7 in the endometrium. Results demonstrate that temporal changes in AA in the ULF reflect changes in transporter expression in the endometrium and conceptus during early pregnancy in cattle, some of which are modified by P4.
在牛中，孕体与母体的相互作用对于妊娠的建立和维持至关重要。这种早期相互作用的一个主要组成部分涉及子宫上皮细胞对营养物质的转运以及关键分子的分泌，以帮助在妊娠植入前期支持孕体发育。研究目的是：1）分析牛发情周期中子宫腔液（ULF）氨基酸（AA）含量的时间变化；2）了解孕体诱导的AA含量变化；3）确定AA转运蛋白在子宫内膜和孕体中的表达；4）确定这些转运蛋白如何受到孕酮（P4）的调节。发情周期第16天，天冬氨酸、精氨酸、谷氨酰胺、组氨酸、赖氨酸、异亮氨酸、亮氨酸、苯丙氨酸和酪氨酸的浓度下降，但在怀孕小母牛的第19天升高（P<0.05）。谷氨酸仅在怀孕小母牛的第19天增加（P<0.001）。在第7天，发情周期的ULF中天冬酰胺浓度高于怀孕小母牛（P<0.05），而在第16天怀孕小母牛的缬氨酸浓度更高（P<0.05）。发情周期/妊娠早期，阳离子AA转运蛋白SLC7A1、SLC7A4和SLC7A6在子宫内膜中的表达随时间变化，与孕体中SLC7A4、SLC7A2和SLC7A1的表达变化一致（P<0.05）。子宫内膜中只有一种酸性AA转运蛋白（SLC1A5）增加，而孕体中SLC1A4的表达增加（P<0.05）。中性AA转运蛋白SLC38A2和SLC7A5在子宫内膜中随时间增加，而孕体中SLC38A7、SLC43A2、SLC38A11和SLC7A8的表达也增加（P<0.05）。P4改变了子宫内膜中SLC1A1、-1A4、-1A5、-38A2、-38A4、-38A7、-43A2、-6A14、-7A1、-7A5和-7A7的表达。结果表明，ULF中AA的时间变化反映了牛妊娠早期子宫内膜和孕体中转运蛋白表达的变化，其中一些受到P4的影响。
