Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin a...Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the scientific literature, the illustrations in this manuscript are drafted as Viking imagery for entertainment purposes.展开更多
Background Recent evidence suggests important roles for progesterone(P4)and interferon tau in the regulation of calcium,phosphate,and vitamin D signaling in the uteri of pregnant sheep.However,the effects of P4 and es...Background Recent evidence suggests important roles for progesterone(P4)and interferon tau in the regulation of calcium,phosphate,and vitamin D signaling in the uteri of pregnant sheep.However,the effects of P4 and estradiol(E2),with respect to the expression of their receptors PGR and ESR1,respectively,in uterine epithelia on mineral signaling during the estrous cycle has not been investigated.Estrous cycles of mature Suffolk ewes were synchronized,prostaglandin F2αwas administered,and ewes were observed for estrus(designated as Day 0)in the presence of vasectomized rams.On Days 1,9,or 14 of the estrous cycle,hysterectomies were performed.Results 25-hydroxyvitamin D was more abundant in plasma from ewes on Day 14 than Day 1(P<0.05).Expression of fibroblast growth factor receptor 2(FGFR2),a disintegrin and metalloprotease 17(ADAM17),and parathyroid hormone-related protein(PTHrP)mRNAs was greater in endometria on Day 9 compared to Days 1 and 14(P<0.01).Similarly,expression of transient receptor potential cation channel subfamily V member 6(TRPV6)mRNA was greater in endometria on Day 9 than Day 1(P<0.05).ATPase plasma membrane Ca^(2+)transporting 4(ATP2B4)and S100 calcium binding protein G(S100G)mRNA expression was greater in endometria on Day 14 than on Days 1 and 9(P<0.01).In contrast,endometrial expression of vitamin D receptor(VDR)mRNA was lower on Days 9 and 14 than Day 1(P<0.01).Expression of klotho(KL)(P<0.05)and cytochrome P450 family 24 subfamily A member 1(CYP24)(P<0.01)mRNAs was lower on Day 14 than Days 1 and 9.ADAM17,FGF23,CYP2R1,CYP27B1,KL,and VDR proteins immunolocalized to the uterine myometrium,blood vessels,and uterine luminal(LE),superficial glandular(sGE),and glandular(GE)epithelia.S100A9 protein was weakly expressed in the uterine myometrium,LE,sGE,and GE.Immunoreactivity of CYP2R1 and KL proteins in uterine LE and sGE was less on Day 1 than on Days 9 and 14.In contrast,S100G protein was expressed exclusively by GE,and immunoreactive S100G protein was less on Day 9.S100A12 protein localized to stromal cells of the uterine stratum spongiosum and blood vessels,but not by uterine epithelial cells.Conclusion Collectively,these results implicate E2,P4,and PGR in the regulation of phosphate,calcium,and vitamin D signaling in cyclic ewes.展开更多
Background:Most embryonic loss in pigs occurs before d 30 of gestation.Dietary supplementation with L-arginine(Arg) during early gestation can enhance the survival and development of conceptuses(embryo/fetus and its e...Background:Most embryonic loss in pigs occurs before d 30 of gestation.Dietary supplementation with L-arginine(Arg) during early gestation can enhance the survival and development of conceptuses(embryo/fetus and its extraembryonic membranes) in gilts.However,the underlying mechanisms remain largely unknown.Methods:Between d 14 and 30 of gestation,each gilt was fed daily 2 kg of a corn-and soybean-meal based diet(12% crude protein) supplemented with either 0.4% Arg(as Arg-HCl) or an isonitrogenous amount of L-alanine(Control).There were 10 gilts per treatment group.On d 30 of gestation,gilts were fed either Arg-HCl or L-alanine 30 min before they were hysterectomized,followed by the collection of placentae,embryos,fetal membranes,and fetal fluids.Amniotic and allantoic fluids were analyzed for nitrite and nitrate [NOx;stable oxidation products of nitric oxide(NO)],polyamines,and amino acids.Placentae were analyzed for syntheses of NO and polyamines,water and amino acid transport,concentrations of amino acid-related metabolites,and the expression of angiogenic factors and aquaporins(AQPs).Results:Compared to the control group,Arg supplementation increased(P < 0.05) the number of viable fetuses by 1.9 per litter,the number and diameter of placental blood vessels(+ 25.9% and + 17.0% respectively),embryonic survival(+ 18.5%),total placental weight(+ 36.5%),the total weight of viable fetuses(+ 33.5%),fetal crown-to-rump length(+ 4.7%),and total allantoic and amniotic fluid volumes(+ 44.6% and + 75.5% respectively).Compared to control gilts,Arg supplementation increased(P < 0.05) placental activities of GTP cyclohydrolase-1(+ 33.1%) and ornithine decarboxylase(+ 29.3%);placental syntheses of NO(+ 26.2%) and polyamines(+ 28.9%);placental concentrations of NOx(+ 22.5%),tetrahydrobiopterin(+ 21.1%),polyamines(+ 20.4%),c AMP(+ 27.7%),and c GMP(+ 24.7%);total amounts of NOx(+ 61.7% to + 96.8%),polyamines(+ 60.7% to + 88.7%),amino acids(+ 39% to + 118%),glucose(+ 60.5% to + 62.6%),and fructose(+ 41.4% to + 57.0%) in fetal fluids;and the placental transport of water(+ 33.9%),Arg(+ 78.4%),glutamine(+ 89.9%),and glycine(+ 89.6%).Furthermore,Arg supplementation increased(P < 0.05) placental m RNA levels for angiogenic factors [VEGFA120(+ 117%),VEGFR1(+ 445%),VEGFR2(+ 373%),PGF(+ 197%),and GCH1(+ 126%)] and AQPs [AQP1(+ 280%),AQP3(+ 137%),AQP5(+ 172%),AQP8(+ 165%),and AQP9(+ 127%)].Conclusion:Supplementing 0.4% Arg to a conventional diet for gilts between d 14 and d 30 of gestation enhanced placental NO and polyamine syntheses,angiogenesis,and water and amino acid transport to improve conceptus development and survival.展开更多
Milk is synthesized by mammary epithelial cel s of lactating mammals. The synthetic capacity of the mammary gland depends largely on the number and efficiency of functional mammary epithelial cel s. Structural develop...Milk is synthesized by mammary epithelial cel s of lactating mammals. The synthetic capacity of the mammary gland depends largely on the number and efficiency of functional mammary epithelial cel s. Structural development of the mammary gland occurs during fetal growth, prepubertal and post-pubertal periods, pregnancy, and lactation under the control of various hormones(particularly estrogen, growth hormone, insulin-like growth factor-I, progesterone, placental lactogen, and prolactin) in a species- and stage-dependent manner. Milk is essential for the growth, development, and health of neonates. Amino acids(AA), present in both free and peptide-bound forms, are the most abundant organic nutrients in the milk of farm animals. Uptake of AA from the arterial blood of the lactating dam is the ultimate source of proteins(primarily β-casein and α-lactalbumin) and bioactive nitrogenous metabolites in milk. Results of recent studies indicate extensive catabolism of branched-chain AA(leucine, isoleucine and valine) and arginine to synthesize glutamate,glutamine, alanine, aspartate, asparagine, proline, and polyamines. The formation of polypeptides from AA is regulated not only by hormones(e.g., prolactin, insulin and glucocorticoids) and the rate of blood flow across the lactating mammary gland, but also by concentrations of AA, lipids, glucose, vitamins and minerals in the maternal plasma, as well as the activation of the mechanistic(mammalian) target rapamycin signaling by certain AA(e.g.,arginine, branched-chain AA, and glutamine). Knowledge of AA utilization(including metabolism) by mammary epithelial cells will enhance our fundamental understanding of lactation biology and has important implications for improving the efficiency of livestock production worldwide.展开更多
Meeting the increasing demands for high-quality pork protein requires not only improved diets but also biotechnology-based breeding to generate swine with desired production traits.Biotechnology can be classified as t...Meeting the increasing demands for high-quality pork protein requires not only improved diets but also biotechnology-based breeding to generate swine with desired production traits.Biotechnology can be classified as the cloning of animals with identical genetic composition or genetic engineering(via recombinant DNA technology and gene editing)to produce genetically modified animals or microorganisms.Cloning helps to conserve species and breeds,particularly those with excellent biological and economical traits.Recombinant DNA technology combines genetic materials from multiple sources into single cells to generate proteins.Gene(genome)editing involves the deletion,insertion or silencing of genes to produce:(a)genetically modified pigs with important production traits;or(b)microorganisms without an ability to resist antimicrobial substances.Current gene-editing tools include the use of zinc finger nuclease(ZFN),transcription activator-like effector nuclease(TALEN),or clustered regularly interspaced short palindromic repeats-associated nuclease-9(CRISPR/Cas9)as editors.ZFN,TALEN,or CRISPR/Cas9 components are delivered into target cells through transfection(lipid-based agents,electroporation,nucleofection,or microinjection)or bacteriophages,depending on cell type and plasmid.Compared to the ZFN and TALEN,CRISPR/Cas9 offers greater ease of design and greater flexibility in genetic engineering,but has a higher frequency of off-target effects.To date,genetically modified pigs have been generated to express bovine growth hormone,bacterial phytase,fungal carbohydrases,plant and C.elagan fatty acid desaturases,and uncoupling protein-1;and to lack myostatin,α-1,3-galactosyltransferase,or CD163(a cellular receptor for the"blue ear disease"virus).Biotechnology holds promise in improving the efficiency of swine production and developing alternatives to antibiotics in the future.展开更多
Background: Polyamines stimulate DNA transcription and m RNA translation for protein synthesis in trophectoderm cells, as well as proliferation and migration of cells; therefore, they are essential for development and...Background: Polyamines stimulate DNA transcription and m RNA translation for protein synthesis in trophectoderm cells, as well as proliferation and migration of cells; therefore, they are essential for development and survival of conceptuses(embryo/fetus and placenta). The ovine conceptus produces polyamines via classical and non-classical pathways. In the classical pathway, arginine(Arg) is transformed into ornithine, which is then decarboxylated by ornithine decarboxylase(ODC1) to produce putrescine which is the substrate for the production of spermidine and spermine. In the non-classical pathway, Arg is converted to agmatine(Agm) by arginine decarboxylase(ADC), and Agm is converted to putrescine by agmatinase(AGMAT).Methods: Morpholino antisense oligonucleotides(MAOs) were designed and synthesized to inhibit translational initiation of the m RNAs for ODC1 and ADC, in ovine conceptuses.Results: The morphologies of MAO control, MAO-ODC1, and MAO-ADC conceptuses were normal. Double knockdown of ODC1 and ADC(MAO-ODC1:ADC) resulted in two phenotypes of conceptuses; 33% of conceptuses appeared to be morphological y and functional y normal(phenotype a) and 67% of the conceptuses presented an abnormal morphology and functionality(phenotype b). Furthermore, MAO-ODC1:ADC(a) conceptuses had greater tissue concentrations of Agm,putrescine, and spermidine than MAO control conceptuses, while MAO-ODC1:ADC(b) conceptuses only had greater tissue concentrations of Agm. Uterine flushes from ewes with MAO-ODC1:ADC(a) had greater amounts of arginine, aspartate, tyrosine, citrulline, lysine, phenylalanine, isoleucine, leucine, and glutamine, while uterine flushes of ewes with MAO-ODC1:ADC(b) conceptuses had lower amount of putrescine, spermidine, spermine, alanine, aspartate,glutamine, tyrosine, phenylalanine, isoleucine, leucine, and lysine.Conclusions: The double-knockdown of translation of ODC1 and ADC m RNAs was most detrimental to conceptus development and their production of interferon tau(IFNT). Agm, polyamines, amino acids, and adequate secretion of IFNT are critical for establishment and maintenance of pregnancy during the peri-implantation period of gestation in sheep.展开更多
Background:Administration of progesterone(P4)to ewes during the first 9 to 12 days of pregnancy accelerates blastocyst development by day 12 of pregnancy,likely due to P4-induced up-regulation of key genes in uterine ...Background:Administration of progesterone(P4)to ewes during the first 9 to 12 days of pregnancy accelerates blastocyst development by day 12 of pregnancy,likely due to P4-induced up-regulation of key genes in uterine epithelia responsible for secretion and transport of components of histotroph into the uterine lumen.This study determined if acceleration of blastocyst development induced by exogenous P4 during the pre-implantation period affects fetal-placental development on day 125 of pregnancy.Suffolk ewes(n=35)were mated to fertile rams and assigned randomly to receive daily intramuscular injections of either corn oil vehicle(CO,n=18)or 25 mg progesterone in CO(P4,n=17)for the first 8 days of pregnancy.All ewes were hysterectomized on day 125 of pregnancy and:1)fetal and placental weights and measurements were recorded;2)endometrial and placental tissues were analyzed for the expression of candidate mRNAs involved in nutrient transport and arginine metabolism;and 3)maternal plasma,fetal plasma,allantoic fluid,and amniotic fluid were analyzed for amino acids,agmatine,polyamines,glucose,and fructose.Results:Treatment of ewes with exogenous P4 did not alter fetal or placental growth,but increased amounts of aspartate and arginine in allantoic fluid and amniotic fluid,respectively.Ewes that received exogenous P4 had greater expression of mRNAs for SLC7A1,SLC7A2,SLC2A1,AGMAT,and ODC1 in endometria,as well as SLC1A4,SLC2A5,SLC2A8 and ODC1 in placentomes.In addition,AZIN2 protein was immunolocalized to uterine luminal and glandular epithelia in P4-treated ewes,whereas AZIN2 localized only to uterine luminal epithelia in CO-treated ewes.Conclusions:This study revealed that exogenous P4 administered in early pregnancy influenced expression of selected genes for nutrient transporters and the expression of a protein involved in polyamine synthesis on day 125 of pregnancy,suggesting a‘programming’effect of P4 on gene expression that affected the composition of nutrients in fetal-placental fluids.展开更多
Background: In recent decades, there has been a growing interest in the impact of insults during pregnancy on postnatal health and disease. It is known that changes in placental development can impact fetal growth and...Background: In recent decades, there has been a growing interest in the impact of insults during pregnancy on postnatal health and disease. It is known that changes in placental development can impact fetal growth and subsequent susceptibility to adult onset diseases;however, a method to collect sufficient placental tissues for both histological and gene expression analyses during gestation without compromising the pregnancy has not been described. The ewe is an established biomedical model for the study of fetal development. Due to its cotyledonary placental type, the sheep has potential for surgical removal of materno-fetal exchange tissues, i.e., placentomes. A novel surgical procedure was developed in well-fed control ewes to excise a single placentome at mid-gestation.Results: A follow-up study was performed in a cohort of nutrient-restricted ewes to investigate rapid placental changes in response to undernutrition. The surgery averaged 19 min, and there were no viability differences between control and sham ewes. Nutrient restricted fetuses were smaller than controls(4.7 ± 0.1 kg vs. 5.6 ± 0.2 kg;P < 0.05), with greater dam weight loss(-32.4 ± 1.3 kg vs. 14.2 ± 2.2 kg;P < 0.01), and smaller placentomes at necropsy(5.7 ± 0.3 g vs. 7.2 ± 0.9 g;P < 0.05). Weight of sampled placentomes and placentome numbers did not differ.Conclusions: With this technique, gestational studies in the sheep model will provide insight into the onset and complexity of changes in gene expression in placentomes resulting from undernutrition(as described in our study),overnutrition, alcohol or substance abuse, and environmental or disease factors of relevance and concern regarding the reproductive health and developmental origins of health and disease in humans and in animals.展开更多
Background:Administration of exogenous progesterone(P4)to ewes during the pre-implantation period advances conceptus development and implantation.This study determined effects of exogenous P4 on transport of select nu...Background:Administration of exogenous progesterone(P4)to ewes during the pre-implantation period advances conceptus development and implantation.This study determined effects of exogenous P4 on transport of select nutrients and pathways that enhance conceptus development.Pregnant ewes(n=38)were treated with either 25 mg P4 in 1 mL corn oil(P4,n=18)or 1mL corn oil alone(CO,n=20)from day 1.5 through day 8 of pregnancy and hysterectomized on either day 9 or day 12 of pregnancy.Endometrial expression of genes encoding enzymes for synthesis of polyamines,transporters of glucose,arginine,and glycine,as well as progestamedins was determined by RT-qPCR.Results:On day 12 of pregnancy,conceptuses from P4-treated ewes had elongated while those from CO-treated ewes were spherical.The mRNA expression of AZIN2,an arginine decarboxylase,was lower in endometria of P4-treated than CO-treated ewes on day 9 of pregnancy.Expression of FGF10,a progestamedin,was greater in endometria of CO and P4-treated ewes on day 12 of gestation in addition to P4-treated ewes necropsied on day 9 of gestation.Treatment with P4 down-regulated endometrial expression of amino acid transporter SLC1A4 on day 12 of pregnancy.Conclusions:Results indicated that administration of exogenous P4 during the pre-implantation period advanced the expression of FGF10,which may accelerate proliferation of trophectoderm cells,but also was correlated with decreased expression of glycine and serine transporters and polyamine synthesis enzyme AZIN2.Further research with increased sample sizes may determine how differential expression affects endometrial functions and potentially embryonic loss.展开更多
Background:The lysosphingolipid,sphingosine-1-phosphate,is a well-described and potent pro-angiogenic factor.Receptors,as well as the sphingosine phosphorylating enzyme sphingosine kinase 1,are expressed in the placen...Background:The lysosphingolipid,sphingosine-1-phosphate,is a well-described and potent pro-angiogenic factor.Receptors,as well as the sphingosine phosphorylating enzyme sphingosine kinase 1,are expressed in the placentomes of sheep and the decidua of rodents;however,a function for this signaling pathway during pregnancy has not been established.The objective of this study was to investigate whether sphingosine-1-phosphate promoted angiogenesis within the placentomes of pregnant ewes.Ewes were given daily jugular injections of FTY720(2-amino-2[2-(−4-octylphenyl)ethyl]propate-1,3-diol hydrochloride),an S1P analog.Results:FTY720 infusion from days 30 to 60 of pregnancy did not alter maternal organ weights nor total number or mass of placentomes,but did alter placentome histoarchitecture.Interdigitation of caruncular crypts and cotyledonary villi was decreased,as was the relative area of cotyledonary tissue within placentomes.Also,the percentage of area occupied by cotyledonary villi per unit of placentome was increased,while the thickness of the caruncular capsule was decreased in ewes treated with FTY720.Further,FTY720 infusion decreased the number and density of blood vessels within caruncular tissue near the placentome capsule where the crypts emerge from the capsule.Finally,FTY720 infusion decreased asparagine and glutamine in amniotic fluid and methionine in allantoic fluid,and decreased the crown rump length of day 60 fetuses.Conclusions:While members of the sphingosine-1-phosphate signaling pathway have been characterized within the uteri and placentae of sheep and mice,the present study uses FTY720 to address the influence of S1P signaling on placental development.We present evidence that modulation of the S1P signaling pathway results in the alteration of caruncular vasculature,placentome architecture,abundance of amino acids in allantoic and amniotic fluids,and fetal growth during pregnancy in sheep.The marked morphological changes in placentome histoarchitecture,including alteration in the vasculature,may be relevant to fetal growth and survival.It is somewhat surprising that fetal length was reduced as early as day 60,because fetal growth in sheep is greatest after day 60.The subtle changes observed in the fetuses of ewes exposed to FTY720 may indicate an adaptive response of the fetuses to cope with altered placental morphology.展开更多
The dialogue between the mammalian conceptus(embryo/fetus and associated membranes) involves signaling for pregnancy recognition and maintenance of pregnancy during the critical peri-implantation period of pregnancy w...The dialogue between the mammalian conceptus(embryo/fetus and associated membranes) involves signaling for pregnancy recognition and maintenance of pregnancy during the critical peri-implantation period of pregnancy when the stage is set for implantation and placentation that precedes fetal development. Uterine epithelial cells secrete and/or transport a wide range of molecules, including nutrients,collectively referred to as histotroph that are transported into the fetal-placental vascular system to support growth and development of the conceptus. The availability of uterine-derived histotroph has long-term consequences for the health and well-being of the fetus and the prevention of adult onset of metabolic diseases. Histotroph includes numerous amino acids, but arginine plays a particularly important role as a source of nitric oxide and polyamines required for fetal-placental development in rodents, swine and humans through mechanisms that remain to be fully elucidated. Mechanisms whereby arginine regulates expression of genes via the mechanistic target of rapamycin cell signaling pathways critical to conceptus development, implantation and placentation are discussed in detail in this review.展开更多
基金supported by USDA-NRICGP 98-35203-6337 to FWB.and RCB,NRSA DHHS/NIH 1-F32-HDO 8501 O1A1 to GAJ,USDA-NRI 2006-35203-17199 to GAJ and Kayla J.BaylessUSDA National Institute of Food and Agriculture Research Initiative Competitive Fellowship Grant no.2012-67011-19892 to James W.Frank and GAJ+1 种基金Agriculture and Food Research Initiative Competitive Grant no.2016-67015-24955 from the USDA National Institute of Food and Agriculture to GAJ and FWBNational Institutes of Health Grant 1R21HD071468-01 to GAJ and KJB。
文摘Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the scientific literature, the illustrations in this manuscript are drafted as Viking imagery for entertainment purposes.
基金supported by Agriculture and Food Research Initiative Competitive Grant 2016-67015-24958 from the USDA National Institute of Food and Agriculture.
文摘Background Recent evidence suggests important roles for progesterone(P4)and interferon tau in the regulation of calcium,phosphate,and vitamin D signaling in the uteri of pregnant sheep.However,the effects of P4 and estradiol(E2),with respect to the expression of their receptors PGR and ESR1,respectively,in uterine epithelia on mineral signaling during the estrous cycle has not been investigated.Estrous cycles of mature Suffolk ewes were synchronized,prostaglandin F2αwas administered,and ewes were observed for estrus(designated as Day 0)in the presence of vasectomized rams.On Days 1,9,or 14 of the estrous cycle,hysterectomies were performed.Results 25-hydroxyvitamin D was more abundant in plasma from ewes on Day 14 than Day 1(P<0.05).Expression of fibroblast growth factor receptor 2(FGFR2),a disintegrin and metalloprotease 17(ADAM17),and parathyroid hormone-related protein(PTHrP)mRNAs was greater in endometria on Day 9 compared to Days 1 and 14(P<0.01).Similarly,expression of transient receptor potential cation channel subfamily V member 6(TRPV6)mRNA was greater in endometria on Day 9 than Day 1(P<0.05).ATPase plasma membrane Ca^(2+)transporting 4(ATP2B4)and S100 calcium binding protein G(S100G)mRNA expression was greater in endometria on Day 14 than on Days 1 and 9(P<0.01).In contrast,endometrial expression of vitamin D receptor(VDR)mRNA was lower on Days 9 and 14 than Day 1(P<0.01).Expression of klotho(KL)(P<0.05)and cytochrome P450 family 24 subfamily A member 1(CYP24)(P<0.01)mRNAs was lower on Day 14 than Days 1 and 9.ADAM17,FGF23,CYP2R1,CYP27B1,KL,and VDR proteins immunolocalized to the uterine myometrium,blood vessels,and uterine luminal(LE),superficial glandular(sGE),and glandular(GE)epithelia.S100A9 protein was weakly expressed in the uterine myometrium,LE,sGE,and GE.Immunoreactivity of CYP2R1 and KL proteins in uterine LE and sGE was less on Day 1 than on Days 9 and 14.In contrast,S100G protein was expressed exclusively by GE,and immunoreactive S100G protein was less on Day 9.S100A12 protein localized to stromal cells of the uterine stratum spongiosum and blood vessels,but not by uterine epithelial cells.Conclusion Collectively,these results implicate E2,P4,and PGR in the regulation of phosphate,calcium,and vitamin D signaling in cyclic ewes.
基金supported by Agriculture and Food Research Initiative Competitive Grant no.2014–05142 from the USDA National Institute of Food and Agriculture.
文摘Background:Most embryonic loss in pigs occurs before d 30 of gestation.Dietary supplementation with L-arginine(Arg) during early gestation can enhance the survival and development of conceptuses(embryo/fetus and its extraembryonic membranes) in gilts.However,the underlying mechanisms remain largely unknown.Methods:Between d 14 and 30 of gestation,each gilt was fed daily 2 kg of a corn-and soybean-meal based diet(12% crude protein) supplemented with either 0.4% Arg(as Arg-HCl) or an isonitrogenous amount of L-alanine(Control).There were 10 gilts per treatment group.On d 30 of gestation,gilts were fed either Arg-HCl or L-alanine 30 min before they were hysterectomized,followed by the collection of placentae,embryos,fetal membranes,and fetal fluids.Amniotic and allantoic fluids were analyzed for nitrite and nitrate [NOx;stable oxidation products of nitric oxide(NO)],polyamines,and amino acids.Placentae were analyzed for syntheses of NO and polyamines,water and amino acid transport,concentrations of amino acid-related metabolites,and the expression of angiogenic factors and aquaporins(AQPs).Results:Compared to the control group,Arg supplementation increased(P < 0.05) the number of viable fetuses by 1.9 per litter,the number and diameter of placental blood vessels(+ 25.9% and + 17.0% respectively),embryonic survival(+ 18.5%),total placental weight(+ 36.5%),the total weight of viable fetuses(+ 33.5%),fetal crown-to-rump length(+ 4.7%),and total allantoic and amniotic fluid volumes(+ 44.6% and + 75.5% respectively).Compared to control gilts,Arg supplementation increased(P < 0.05) placental activities of GTP cyclohydrolase-1(+ 33.1%) and ornithine decarboxylase(+ 29.3%);placental syntheses of NO(+ 26.2%) and polyamines(+ 28.9%);placental concentrations of NOx(+ 22.5%),tetrahydrobiopterin(+ 21.1%),polyamines(+ 20.4%),c AMP(+ 27.7%),and c GMP(+ 24.7%);total amounts of NOx(+ 61.7% to + 96.8%),polyamines(+ 60.7% to + 88.7%),amino acids(+ 39% to + 118%),glucose(+ 60.5% to + 62.6%),and fructose(+ 41.4% to + 57.0%) in fetal fluids;and the placental transport of water(+ 33.9%),Arg(+ 78.4%),glutamine(+ 89.9%),and glycine(+ 89.6%).Furthermore,Arg supplementation increased(P < 0.05) placental m RNA levels for angiogenic factors [VEGFA120(+ 117%),VEGFR1(+ 445%),VEGFR2(+ 373%),PGF(+ 197%),and GCH1(+ 126%)] and AQPs [AQP1(+ 280%),AQP3(+ 137%),AQP5(+ 172%),AQP8(+ 165%),and AQP9(+ 127%)].Conclusion:Supplementing 0.4% Arg to a conventional diet for gilts between d 14 and d 30 of gestation enhanced placental NO and polyamine syntheses,angiogenesis,and water and amino acid transport to improve conceptus development and survival.
基金supported by Texas A&M Agri Life Research (H-8200)The Agriculture and Food Research Initiative Competitive Grant from the Animal Growth & Nutrient Utilization Program of the USDA National Institute of Food and Agriculture (2014-67015-21770)+4 种基金National Basic Research Program of China (2012CB126305)National Natural Science Foundation of China (31572412 and 31272450)the 111 Project (B16044)Natural Science Foundation of Hubei Province (2013CFA097 and 2013CFB325)Hubei Hundred Talent program
文摘Milk is synthesized by mammary epithelial cel s of lactating mammals. The synthetic capacity of the mammary gland depends largely on the number and efficiency of functional mammary epithelial cel s. Structural development of the mammary gland occurs during fetal growth, prepubertal and post-pubertal periods, pregnancy, and lactation under the control of various hormones(particularly estrogen, growth hormone, insulin-like growth factor-I, progesterone, placental lactogen, and prolactin) in a species- and stage-dependent manner. Milk is essential for the growth, development, and health of neonates. Amino acids(AA), present in both free and peptide-bound forms, are the most abundant organic nutrients in the milk of farm animals. Uptake of AA from the arterial blood of the lactating dam is the ultimate source of proteins(primarily β-casein and α-lactalbumin) and bioactive nitrogenous metabolites in milk. Results of recent studies indicate extensive catabolism of branched-chain AA(leucine, isoleucine and valine) and arginine to synthesize glutamate,glutamine, alanine, aspartate, asparagine, proline, and polyamines. The formation of polypeptides from AA is regulated not only by hormones(e.g., prolactin, insulin and glucocorticoids) and the rate of blood flow across the lactating mammary gland, but also by concentrations of AA, lipids, glucose, vitamins and minerals in the maternal plasma, as well as the activation of the mechanistic(mammalian) target rapamycin signaling by certain AA(e.g.,arginine, branched-chain AA, and glutamine). Knowledge of AA utilization(including metabolism) by mammary epithelial cells will enhance our fundamental understanding of lactation biology and has important implications for improving the efficiency of livestock production worldwide.
基金supported by Agriculture and Food Research Initiative Competitive Grants(2014–67015-21770,2015–67015-23276,2016–67015-24958,and 2018–505706-95720)from the USDA National Institute of Food and Agriculture,and Texas A&M Agri Life Research(H-8200)
文摘Meeting the increasing demands for high-quality pork protein requires not only improved diets but also biotechnology-based breeding to generate swine with desired production traits.Biotechnology can be classified as the cloning of animals with identical genetic composition or genetic engineering(via recombinant DNA technology and gene editing)to produce genetically modified animals or microorganisms.Cloning helps to conserve species and breeds,particularly those with excellent biological and economical traits.Recombinant DNA technology combines genetic materials from multiple sources into single cells to generate proteins.Gene(genome)editing involves the deletion,insertion or silencing of genes to produce:(a)genetically modified pigs with important production traits;or(b)microorganisms without an ability to resist antimicrobial substances.Current gene-editing tools include the use of zinc finger nuclease(ZFN),transcription activator-like effector nuclease(TALEN),or clustered regularly interspaced short palindromic repeats-associated nuclease-9(CRISPR/Cas9)as editors.ZFN,TALEN,or CRISPR/Cas9 components are delivered into target cells through transfection(lipid-based agents,electroporation,nucleofection,or microinjection)or bacteriophages,depending on cell type and plasmid.Compared to the ZFN and TALEN,CRISPR/Cas9 offers greater ease of design and greater flexibility in genetic engineering,but has a higher frequency of off-target effects.To date,genetically modified pigs have been generated to express bovine growth hormone,bacterial phytase,fungal carbohydrases,plant and C.elagan fatty acid desaturases,and uncoupling protein-1;and to lack myostatin,α-1,3-galactosyltransferase,or CD163(a cellular receptor for the"blue ear disease"virus).Biotechnology holds promise in improving the efficiency of swine production and developing alternatives to antibiotics in the future.
基金supported primarily by the Agriculture and Food Research Initiative Competitive Grants(2016-67,015-24,958 to Fuller W.Bazer and 2015-67,015-23,276 to Guoyao Wu)from the United States Department of Agriculture,National Institute of Food and Agriculturesupported by funding from the Sustainability Strategy2013–2014,from CODI University of Antioquia(Ude A),Medellín,Colombia Scholarship“Becas Doctorado Ude A 2014.”
文摘Background: Polyamines stimulate DNA transcription and m RNA translation for protein synthesis in trophectoderm cells, as well as proliferation and migration of cells; therefore, they are essential for development and survival of conceptuses(embryo/fetus and placenta). The ovine conceptus produces polyamines via classical and non-classical pathways. In the classical pathway, arginine(Arg) is transformed into ornithine, which is then decarboxylated by ornithine decarboxylase(ODC1) to produce putrescine which is the substrate for the production of spermidine and spermine. In the non-classical pathway, Arg is converted to agmatine(Agm) by arginine decarboxylase(ADC), and Agm is converted to putrescine by agmatinase(AGMAT).Methods: Morpholino antisense oligonucleotides(MAOs) were designed and synthesized to inhibit translational initiation of the m RNAs for ODC1 and ADC, in ovine conceptuses.Results: The morphologies of MAO control, MAO-ODC1, and MAO-ADC conceptuses were normal. Double knockdown of ODC1 and ADC(MAO-ODC1:ADC) resulted in two phenotypes of conceptuses; 33% of conceptuses appeared to be morphological y and functional y normal(phenotype a) and 67% of the conceptuses presented an abnormal morphology and functionality(phenotype b). Furthermore, MAO-ODC1:ADC(a) conceptuses had greater tissue concentrations of Agm,putrescine, and spermidine than MAO control conceptuses, while MAO-ODC1:ADC(b) conceptuses only had greater tissue concentrations of Agm. Uterine flushes from ewes with MAO-ODC1:ADC(a) had greater amounts of arginine, aspartate, tyrosine, citrulline, lysine, phenylalanine, isoleucine, leucine, and glutamine, while uterine flushes of ewes with MAO-ODC1:ADC(b) conceptuses had lower amount of putrescine, spermidine, spermine, alanine, aspartate,glutamine, tyrosine, phenylalanine, isoleucine, leucine, and lysine.Conclusions: The double-knockdown of translation of ODC1 and ADC m RNAs was most detrimental to conceptus development and their production of interferon tau(IFNT). Agm, polyamines, amino acids, and adequate secretion of IFNT are critical for establishment and maintenance of pregnancy during the peri-implantation period of gestation in sheep.
基金This research was supported by Agriculture and Food Research Initiative Competitive Grant no.2016-67015-24958 from the USDA National Institute of Food and AgricultureThis research was supported by Agriculture and Food Research Initiative Competitive Grant no.2016-67015-24958 from the USDA National Institute of Food and Agriculture.
文摘Background:Administration of progesterone(P4)to ewes during the first 9 to 12 days of pregnancy accelerates blastocyst development by day 12 of pregnancy,likely due to P4-induced up-regulation of key genes in uterine epithelia responsible for secretion and transport of components of histotroph into the uterine lumen.This study determined if acceleration of blastocyst development induced by exogenous P4 during the pre-implantation period affects fetal-placental development on day 125 of pregnancy.Suffolk ewes(n=35)were mated to fertile rams and assigned randomly to receive daily intramuscular injections of either corn oil vehicle(CO,n=18)or 25 mg progesterone in CO(P4,n=17)for the first 8 days of pregnancy.All ewes were hysterectomized on day 125 of pregnancy and:1)fetal and placental weights and measurements were recorded;2)endometrial and placental tissues were analyzed for the expression of candidate mRNAs involved in nutrient transport and arginine metabolism;and 3)maternal plasma,fetal plasma,allantoic fluid,and amniotic fluid were analyzed for amino acids,agmatine,polyamines,glucose,and fructose.Results:Treatment of ewes with exogenous P4 did not alter fetal or placental growth,but increased amounts of aspartate and arginine in allantoic fluid and amniotic fluid,respectively.Ewes that received exogenous P4 had greater expression of mRNAs for SLC7A1,SLC7A2,SLC2A1,AGMAT,and ODC1 in endometria,as well as SLC1A4,SLC2A5,SLC2A8 and ODC1 in placentomes.In addition,AZIN2 protein was immunolocalized to uterine luminal and glandular epithelia in P4-treated ewes,whereas AZIN2 localized only to uterine luminal epithelia in CO-treated ewes.Conclusions:This study revealed that exogenous P4 administered in early pregnancy influenced expression of selected genes for nutrient transporters and the expression of a protein involved in polyamine synthesis on day 125 of pregnancy,suggesting a‘programming’effect of P4 on gene expression that affected the composition of nutrients in fetal-placental fluids.
文摘Background: In recent decades, there has been a growing interest in the impact of insults during pregnancy on postnatal health and disease. It is known that changes in placental development can impact fetal growth and subsequent susceptibility to adult onset diseases;however, a method to collect sufficient placental tissues for both histological and gene expression analyses during gestation without compromising the pregnancy has not been described. The ewe is an established biomedical model for the study of fetal development. Due to its cotyledonary placental type, the sheep has potential for surgical removal of materno-fetal exchange tissues, i.e., placentomes. A novel surgical procedure was developed in well-fed control ewes to excise a single placentome at mid-gestation.Results: A follow-up study was performed in a cohort of nutrient-restricted ewes to investigate rapid placental changes in response to undernutrition. The surgery averaged 19 min, and there were no viability differences between control and sham ewes. Nutrient restricted fetuses were smaller than controls(4.7 ± 0.1 kg vs. 5.6 ± 0.2 kg;P < 0.05), with greater dam weight loss(-32.4 ± 1.3 kg vs. 14.2 ± 2.2 kg;P < 0.01), and smaller placentomes at necropsy(5.7 ± 0.3 g vs. 7.2 ± 0.9 g;P < 0.05). Weight of sampled placentomes and placentome numbers did not differ.Conclusions: With this technique, gestational studies in the sheep model will provide insight into the onset and complexity of changes in gene expression in placentomes resulting from undernutrition(as described in our study),overnutrition, alcohol or substance abuse, and environmental or disease factors of relevance and concern regarding the reproductive health and developmental origins of health and disease in humans and in animals.
基金This research was supported by Agriculture and Food Research Initiative Competitive Grant no.2016-67015-24958 from the USDA National Institute of Food and Agriculture。
文摘Background:Administration of exogenous progesterone(P4)to ewes during the pre-implantation period advances conceptus development and implantation.This study determined effects of exogenous P4 on transport of select nutrients and pathways that enhance conceptus development.Pregnant ewes(n=38)were treated with either 25 mg P4 in 1 mL corn oil(P4,n=18)or 1mL corn oil alone(CO,n=20)from day 1.5 through day 8 of pregnancy and hysterectomized on either day 9 or day 12 of pregnancy.Endometrial expression of genes encoding enzymes for synthesis of polyamines,transporters of glucose,arginine,and glycine,as well as progestamedins was determined by RT-qPCR.Results:On day 12 of pregnancy,conceptuses from P4-treated ewes had elongated while those from CO-treated ewes were spherical.The mRNA expression of AZIN2,an arginine decarboxylase,was lower in endometria of P4-treated than CO-treated ewes on day 9 of pregnancy.Expression of FGF10,a progestamedin,was greater in endometria of CO and P4-treated ewes on day 12 of gestation in addition to P4-treated ewes necropsied on day 9 of gestation.Treatment with P4 down-regulated endometrial expression of amino acid transporter SLC1A4 on day 12 of pregnancy.Conclusions:Results indicated that administration of exogenous P4 during the pre-implantation period advanced the expression of FGF10,which may accelerate proliferation of trophectoderm cells,but also was correlated with decreased expression of glycine and serine transporters and polyamine synthesis enzyme AZIN2.Further research with increased sample sizes may determine how differential expression affects endometrial functions and potentially embryonic loss.
基金National Research Initiative Competitive Grant No.2009-35203-05725(KJB and GAJ)Fellowship No.2008-35203-18830(KAD)from the USDA National Institute of Food and Agriculture.
文摘Background:The lysosphingolipid,sphingosine-1-phosphate,is a well-described and potent pro-angiogenic factor.Receptors,as well as the sphingosine phosphorylating enzyme sphingosine kinase 1,are expressed in the placentomes of sheep and the decidua of rodents;however,a function for this signaling pathway during pregnancy has not been established.The objective of this study was to investigate whether sphingosine-1-phosphate promoted angiogenesis within the placentomes of pregnant ewes.Ewes were given daily jugular injections of FTY720(2-amino-2[2-(−4-octylphenyl)ethyl]propate-1,3-diol hydrochloride),an S1P analog.Results:FTY720 infusion from days 30 to 60 of pregnancy did not alter maternal organ weights nor total number or mass of placentomes,but did alter placentome histoarchitecture.Interdigitation of caruncular crypts and cotyledonary villi was decreased,as was the relative area of cotyledonary tissue within placentomes.Also,the percentage of area occupied by cotyledonary villi per unit of placentome was increased,while the thickness of the caruncular capsule was decreased in ewes treated with FTY720.Further,FTY720 infusion decreased the number and density of blood vessels within caruncular tissue near the placentome capsule where the crypts emerge from the capsule.Finally,FTY720 infusion decreased asparagine and glutamine in amniotic fluid and methionine in allantoic fluid,and decreased the crown rump length of day 60 fetuses.Conclusions:While members of the sphingosine-1-phosphate signaling pathway have been characterized within the uteri and placentae of sheep and mice,the present study uses FTY720 to address the influence of S1P signaling on placental development.We present evidence that modulation of the S1P signaling pathway results in the alteration of caruncular vasculature,placentome architecture,abundance of amino acids in allantoic and amniotic fluids,and fetal growth during pregnancy in sheep.The marked morphological changes in placentome histoarchitecture,including alteration in the vasculature,may be relevant to fetal growth and survival.It is somewhat surprising that fetal length was reduced as early as day 60,because fetal growth in sheep is greatest after day 60.The subtle changes observed in the fetuses of ewes exposed to FTY720 may indicate an adaptive response of the fetuses to cope with altered placental morphology.
基金supported by National Research Initiative Competitive Grants from the Animal Reproduction Program (2008-35203-19120, 2009-35206-05211, 201167015-20067, and 2011-67015-20028)Animal Growth & Nutrient Utilization Program (2008-35206-18764) of the USDA National Institute of Food and AgricultureTexas A&M Agri Life Research (H-8200)
文摘The dialogue between the mammalian conceptus(embryo/fetus and associated membranes) involves signaling for pregnancy recognition and maintenance of pregnancy during the critical peri-implantation period of pregnancy when the stage is set for implantation and placentation that precedes fetal development. Uterine epithelial cells secrete and/or transport a wide range of molecules, including nutrients,collectively referred to as histotroph that are transported into the fetal-placental vascular system to support growth and development of the conceptus. The availability of uterine-derived histotroph has long-term consequences for the health and well-being of the fetus and the prevention of adult onset of metabolic diseases. Histotroph includes numerous amino acids, but arginine plays a particularly important role as a source of nitric oxide and polyamines required for fetal-placental development in rodents, swine and humans through mechanisms that remain to be fully elucidated. Mechanisms whereby arginine regulates expression of genes via the mechanistic target of rapamycin cell signaling pathways critical to conceptus development, implantation and placentation are discussed in detail in this review.
基金Project supported by the National Basic Research Program(973)of China(No.2012CB124703)the National Natural Science Foundation of China(Nos.31129006,31272449,and 31422052)
