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Placental accommodations for transport and metabolism during intra-uterine crowding in pigs 被引量:7
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作者 Jeffrey L Vallet Anthony K Mc Neel +1 位作者 Jeremy R Miles Bradley A Freking 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2015年第2期163-176,共14页
Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. Uterine capacity is the result of the combined... Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. Uterine capacity is the result of the combined effects of uterine, placental and embryo/fetal function. The number of living conceptuses that the uterus is capable of supporting is greater during early gestation compared to later gestation. Plots of log fetal weight versus log placental weight also indicate that fetal weights are less sensitive to reduced placental weight (and therefore reduced intrauterine space) in early gestation compared to late gestation. However, even in late gestation, mechanisms still exist that maintain fetal growth when the size of the placenta is reduced. One such mechanism is likely to be improved development of the folded placental-epithelial/maternal-epithelial bilayer. Fold depth, and therefore the maternal fetal interactive surface, increases as gestation advances and is greater in placenta from smal fetuses. On the fetal side of the placenta, the epithelial bilayer is embedded in stromal tissue. Glycosaminoglycans are major components of stroma, including hyaluronan and heparan sulfate. Hyaluronidases and heparanases are present within placental tissues, and likely play roles in modification of stromal components to facilitate fold development. Glycosaminoglycans are polymers of forms of glucose (glucosamine, glucuronic acid, iduronic acid) suggesting that glycosaminoglycan synthesis may compete with the glucose needs of the developing fetus. Pig conceptuses are fructogenic, such that a substantial portion of glucose transferred from mother to fetus is converted to fructose. Fructose is an intermediate product in the synthesis of glucosamine from glucose, and glucosamine is linked to regulation of trophoblast cell proliferation through regulation of mTOR. These findings suggest a link between glucose, fructose, glucosamine synthesis, GAG production, and placental morphogenesis, but the details of these interactions remain unclear. In addition, recent placental epithelial transcriptome analysis identified several glucose, amino acid, lipid, vitamin, mineral and hormone transporter mechanisms within the placenta. Further elucidation of mechanisms of placental morphogenesis and solute transport could provide clues to improving nutrient transport to the pig fetus, potentially increasing litter size and piglet birth weights. 展开更多
关键词 glycosaminoglycans nutrient transport placenta
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Factors controlling nutrient availability to the developing fetus in ruminants 被引量:1
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作者 Kathrin A Dunlap Jacob D Brown +1 位作者 Ashley B Keith M Carey Satterfield 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2015年第2期205-214,共10页
Inadequate delivery of nutrients results in intrauterine growth restriction (IUGR), which is a leading cause of neonatal morbidity and mortality in livestock. In ruminants, inadequate nutrition during pregnancy is o... Inadequate delivery of nutrients results in intrauterine growth restriction (IUGR), which is a leading cause of neonatal morbidity and mortality in livestock. In ruminants, inadequate nutrition during pregnancy is often prevalent due to frequent utilization of exensive forage based grazing systems, making them highly susceptible to changes in nutrient quality and availability. Delivery of nutrients to the fetus is dependent on a number of critical factors including placental growth and development, utero-placental blood flow, nutrient availability, and placenta metabolism and transport capacity. Previous findings from our laboratory and others, highlight essential roles for amino acids and their metabolites in supporting normal fetal growth and development, as well as the critical role for amino acid transporters in nutrient delivery to the fetus. The focus of this review will be on the role of materna nutrition on placental form and function as a regulator of fetal development in ruminants. 展开更多
关键词 Intrauterine growth restriction nutrient transport placenta RUMINANT
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柯乐猪和大白猪胎盘发育与繁殖性能的相关性分析 被引量:5
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作者 胡光玲 申涛 +3 位作者 伍治敏 谭元成 张依裕 敖政 《畜牧与兽医》 CAS 北大核心 2023年第6期1-10,共10页
旨在探讨柯乐猪与大白猪胎盘组织形态及营养转运、血管生成、抗氧化应激和细胞凋亡与其繁殖性能差异的相关性。比较大白猪与柯乐猪窝均产仔数、产活仔率、初生重、胎盘绒毛数量、血管数量,以及胎盘营养转运、血管生成、抗氧化应激、细... 旨在探讨柯乐猪与大白猪胎盘组织形态及营养转运、血管生成、抗氧化应激和细胞凋亡与其繁殖性能差异的相关性。比较大白猪与柯乐猪窝均产仔数、产活仔率、初生重、胎盘绒毛数量、血管数量,以及胎盘营养转运、血管生成、抗氧化应激、细胞凋亡相关基因的mRNA表达水平。结果显示:柯乐猪的窝均产仔数、产活仔率和平均初生重均显著低于大白猪(P<0.05);通过组织形态学分析发现,柯乐猪胎盘相较于大白猪表现为绒毛数量不足和发育不良;实时荧光定量PCR显示,柯乐猪胎盘中葡萄糖转运基因溶质载体家族2成员1(SLC2A1)和氨基酸转运基因溶质载体家族38成员10(SLC38A10),抗氧化应激相关基因铜锌超氧化物歧化酶(CuZn-SOD)、锰超氧化物歧化酶(Mn-SOD)和过氧化氢酶(CAT),抗细胞凋亡基因B淋巴细胞瘤-2基因(BCL-2)的转录水平显著低于大白猪胎盘(P<0.05),而脂肪酸转运蛋白4(FATP4)的转录水平显著高于大白猪胎盘(P<0.05);柯乐猪胎盘中超氧化物歧化酶(SOD)、CAT酶活性显著低于大白猪胎盘(P<0.05),而活性氧(ROS)自由基水平显著高于大白猪胎盘(P<0.05);通过TUNEL分析显示,柯乐猪胎盘组织的细胞凋亡水平极显著高于大白猪胎盘(P<0.01)。结论:胎盘组织形态发育不良以及营养转运、抗氧化、抗凋亡能力不足可能是造成柯乐猪胎儿数量少和初生重低的重要原因,这可为探究柯乐猪繁殖性能的调控机制提供重要依据。 展开更多
关键词 柯乐猪 初生重 胎盘 营养转运 抗氧化应激
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高脂日粮通过非编码RNAs调控哺乳动物胎盘养分转运的研究进展
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作者 陈青云 何天乐 杨震国 《黑龙江畜牧兽医》 CAS 北大核心 2023年第2期31-36,42,共7页
胎儿生长发育和生理状况与母体营养水平及胎盘养分转运能力密切相关。在妊娠期给母体饲喂高脂日粮可能影响母体健康和胎儿宫内发育状况,同时对后代长期健康和新陈代谢方面也有重要影响。随着高通量RNA测序(RNA-Seq)技术的兴起,部分非编... 胎儿生长发育和生理状况与母体营养水平及胎盘养分转运能力密切相关。在妊娠期给母体饲喂高脂日粮可能影响母体健康和胎儿宫内发育状况,同时对后代长期健康和新陈代谢方面也有重要影响。随着高通量RNA测序(RNA-Seq)技术的兴起,部分非编码RNAs(non-coding RNAs)调控哺乳动物机体细胞增殖与分化等多个生理学过程的机制得以阐明。笔者综述了高脂日粮通过环状RNAs(circRNAs)、长链非编码RNAs(lncRNAs)和微小RNAs(miRNAs)影响母体胎盘养分转运的研究进展,并阐述了circRNAs、lncRNAs及miRNAs在哺乳动物孕期饲喂高脂日粮对胎盘养分转运的具体调控机制,为预防哺乳动物孕期肥胖并促进胎儿健康生长提供一定的理论依据,同时为非编码RNA参与机体生命活动和物质代谢奠定理论基础。 展开更多
关键词 高脂日粮 胎盘 养分 转运 环状RNAs 长链非编码RNAs 微小RNAS
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印记基因对动物胎盘调控的研究进展 被引量:2
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作者 康倩 崔焕忠 +3 位作者 孙玉成 高云航 范译文 刘二战 《畜牧兽医学报》 CAS CSCD 北大核心 2013年第2期169-173,共5页
印记基因是仅表达亲本一方遗传信息的一类基因。通过大量的研究表明,印记基因对胎儿、胎盘的生长发育及胎儿出生后行为等方面的调控都具有显著作用。印记基因具有决定胎盘运输能力的作用,并能调节胎盘的生长、形态和转运能力。当胎盘所... 印记基因是仅表达亲本一方遗传信息的一类基因。通过大量的研究表明,印记基因对胎儿、胎盘的生长发育及胎儿出生后行为等方面的调控都具有显著作用。印记基因具有决定胎盘运输能力的作用,并能调节胎盘的生长、形态和转运能力。当胎盘所处环境或胎盘表型发生变化时,印记基因能够通过改变胎盘一定的表观遗传状态来适应当时的营养环境。印记基因类似营养传感器能优化胎儿获得营养。印记基因对胎盘的表观遗传具有重要调控作用。 展开更多
关键词 胎盘 生长发育 营养运输 印记基因 表观遗传学
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