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Rosario FJ, Barentsen K, Powell TL, Urschitz J, Brown TL, Kanai Y, Jansson T. Trophoblast-specific overexpression of the LAT1 increases transplacental transport of essential amino acids and fetal growth in mice. PNAS NEXUS 2024; 3:pgae207. [PMID: 38894879 PMCID: PMC11184900 DOI: 10.1093/pnasnexus/pgae207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 05/17/2024] [Indexed: 06/21/2024]
Abstract
Placental System L amino acid transporter activity is decreased in pregnancies complicated by intrauterine growth restriction (IUGR) and increased in fetal overgrowth. However, it is unknown if changes in the expression/activity of placental Large Neutral Amino Acid Transporter Small Subunit 1 (Slc7a5/LAT1) are mechanistically linked to placental function and fetal growth. We hypothesized that trophoblast-specific Slc7a5 overexpression increases placental transport of essential amino acids, activates the placental mechanistic target of rapamycin (mTOR) signaling, and promotes fetal growth in mice. Using lentiviral transduction of blastocysts with a Slc7a5 transgene, we achieved trophoblast-specific overexpression of Slc7a5 (Slc7a5 OX) with increased fetal (+27%) and placental weights (+10%). Trophoblast-specific Slc7a5 overexpression increased trophoblast plasma membrane (TPM) LAT1 protein abundance and TPM System L transporter (+53%) and System A transporter activity (+ 21%). Slc7a5 overexpression also increased transplacental transport of leucine (+ 85%) but not of the System A tracer, 14C-methylamino isobutyric acid, in vivo. Trophoblast-specific overexpression of Slc7a5 activated placental mTORC1, as assessed by increased (+44%) phosphorylation of S6 ribosomal protein (Ser 235/236), and mTORC2 as indicated by phosphorylation of PKCα-Tyr-657 (+47%) and Akt-Ser 473 (+96%). This is the first demonstration that placental transport of essential amino acids is mechanistically linked to fetal growth. The decreased placental System L activity in human IUGR and the increased placental activity of this transporter in some cases of fetal overgrowth may directly contribute to the development of these pregnancy complications.
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Affiliation(s)
- Fredrick J Rosario
- Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kenneth Barentsen
- Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Theresa L Powell
- Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
- Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Johann Urschitz
- Institue of Biogenesis, University of Hawaii, Honolulu, HI 96822, USA
| | - Thomas L Brown
- Department of Neuroscience, Cell Biology, and Physiology, Wright State University Boonshoft School of Medicine, Dayton, OH 45435, USA
| | - Yoshikatsu Kanai
- Department of Bio-system Pharmacology, Graduate School of Medicine, Osaka University, Osaka, 565-0871, Japan
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
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2
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Baker BH, Freije S, MacDonald JW, Bammler TK, Benson C, Carroll KN, Enquobahrie DA, Karr CJ, LeWinn KZ, Zhao Q, Bush NR, Sathyanarayana S, Paquette AG. Placental transcriptomic signatures of prenatal and preconceptional maternal stress. Mol Psychiatry 2024; 29:1179-1191. [PMID: 38212375 PMCID: PMC11176062 DOI: 10.1038/s41380-023-02403-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/13/2024]
Abstract
Prenatal exposure to maternal psychological stress is associated with increased risk for adverse birth and child health outcomes. Accumulating evidence suggests that preconceptional maternal stress may also be transmitted intergenerationally to negatively impact offspring. However, understanding of mechanisms linking these exposures to offspring outcomes, particularly those related to placenta, is limited. Using RNA sequencing, we identified placental transcriptomic signatures associated with maternal prenatal stressful life events (SLEs) and childhood traumatic events (CTEs) in 1 029 mother-child pairs in two birth cohorts from Washington state and Memphis, Tennessee. We evaluated individual gene-SLE/CTE associations and performed an ensemble of gene set enrichment analyses combing across 11 popular enrichment methods. Higher number of prenatal SLEs was significantly (FDR < 0.05) associated with increased expression of ADGRG6, a placental tissue-specific gene critical in placental remodeling, and decreased expression of RAB11FIP3, an endocytosis and endocytic recycling gene, and SMYD5, a histone methyltransferase. Prenatal SLEs and maternal CTEs were associated with gene sets related to several biological pathways, including upregulation of protein processing in the endoplasmic reticulum, protein secretion, and ubiquitin mediated proteolysis, and down regulation of ribosome, epithelial mesenchymal transition, DNA repair, MYC targets, and amino acid-related pathways. The directional associations in these pathways corroborate prior non-transcriptomic mechanistic studies of psychological stress and mental health disorders, and have previously been implicated in pregnancy complications and adverse birth outcomes. Accordingly, our findings suggest that maternal exposure to psychosocial stressors during pregnancy as well as the mother's childhood may disrupt placental function, which may ultimately contribute to adverse pregnancy, birth, and child health outcomes.
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Affiliation(s)
- Brennan H Baker
- University of Washington, Seattle, WA, USA.
- Seattle Children's Research Institute, Seattle, WA, USA.
| | | | | | | | - Ciara Benson
- Global Alliance to Prevent Preterm Birth and Stillbirth (GAPPS), Lynnwood, WA, USA
| | | | | | | | - Kaja Z LeWinn
- University of California San Francisco, San Francisco, CA, USA
| | - Qi Zhao
- University of Tennessee Health Sciences Center, Memphis, TN, USA
| | - Nicole R Bush
- University of California San Francisco, San Francisco, CA, USA
| | - Sheela Sathyanarayana
- University of Washington, Seattle, WA, USA
- Seattle Children's Research Institute, Seattle, WA, USA
| | - Alison G Paquette
- University of Washington, Seattle, WA, USA
- Seattle Children's Research Institute, Seattle, WA, USA
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3
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Rosario FJ, Urschitz J, Powell TL, Brown TL, Jansson T. Overexpression of the LAT1 in primary human trophoblast cells increases the uptake of essential amino acids and activates mTOR signaling. Clin Sci (Lond) 2023; 137:1651-1664. [PMID: 37861075 DOI: 10.1042/cs20230490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 10/16/2023] [Accepted: 10/19/2023] [Indexed: 10/21/2023]
Abstract
The System L amino acid transporter, particularly the isoform Large Neutral Amino Acid Transporter Small Subunit 1 (LAT1) encoded by SLC7A5, is believed to mediate the transfer of essential amino acids in the human placenta. Placental System L amino acid transporter expression and activity is decreased in pregnancies complicated by IUGR and increased in fetal overgrowth. However, it remains unknown if changes in the expression of LAT1 are mechanistically linked to System L amino acid transport activity. Here, we combined overexpression approaches with protein analysis and functional studies in cultured primary human trophoblast (PHT) cells to test the hypothesis that SLC7A5 overexpression increases the uptake of essential amino acids and activates mTOR signaling in PHT cells. Overexpression of SLC7A5 resulted in a marked increase in protein expression of LAT1 in the PHT cells microvillous plasma membrane and System L amino acid transporter activity. Moreover, mTOR signaling was activated, and System A amino acid transporter activity increased following SLC7A5 overexpression, suggesting coordination of trophoblast amino transporter expression and activity to ensure balanced nutrient flux to the fetus. This is the first report showing that overexpression of LAT1 is sufficient to increase the uptake of essential amino acids in PHT cells, which activates mTOR, a master regulator of placental function. The decreased placental System L activity in human IUGR and the increased placental activity of this transporter system in some cases of fetal overgrowth may directly contribute to changes in fetal amino acid availability and altered fetal growth in these pregnancy complications.
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Affiliation(s)
- Fredrick J Rosario
- Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus, Aurora, CO, U.S.A
| | - Johann Urschitz
- Institute for Biogenesis Research, University of Hawaii, Honolulu, HI, U.S.A
| | - Theresa L Powell
- Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus, Aurora, CO, U.S.A
- Institute for Biogenesis Research, University of Hawaii, Honolulu, HI, U.S.A
| | - Thomas L Brown
- Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A
- Department of Neuroscience, Cell Biology, and Physiology, Wright State University Boonshoft School of Medicine, Dayton, OH, U.S.A
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus, Aurora, CO, U.S.A
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4
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Kramer AC, Jansson T, Bale TL, Powell TL. Maternal-fetal cross-talk via the placenta: influence on offspring development and metabolism. Development 2023; 150:dev202088. [PMID: 37831056 PMCID: PMC10617615 DOI: 10.1242/dev.202088] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Compelling epidemiological and animal experimental data demonstrate that cardiometabolic and neuropsychiatric diseases originate in a suboptimal intrauterine environment. Here, we review evidence suggesting that altered placental function may, at least in part, mediate the link between the maternal environment and changes in fetal growth and development. Emerging evidence indicates that the placenta controls the development and function of several fetal tissues through nutrient sensing, modulation of trophoblast nutrient transporters and by altering the number and cargo of released extracellular vesicles. In this Review, we discuss the development and functions of the maternal-placental-fetal interface (in humans and mice) and how cross-talk between these compartments may be a mechanism for in utero programming, focusing on mechanistic target of rapamycin (mTOR), adiponectin and O-GlcNac transferase (OGT) signaling. We also discuss how maternal diet and stress influences fetal development and metabolism and how fetal growth restriction can result in susceptibility to developing chronic disease later in life. Finally, we speculate how interventions targeting placental function may offer unprecedented opportunities to prevent cardiometabolic disease in future generations.
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Affiliation(s)
- Avery C. Kramer
- Departments of Obstetrics & Gynecology, Psychiatry and Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA
| | - Thomas Jansson
- Departments of Obstetrics & Gynecology, Psychiatry and Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA
| | - Tracy L. Bale
- Departments of Obstetrics & Gynecology, Psychiatry and Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA
| | - Theresa L. Powell
- Departments of Obstetrics & Gynecology, Psychiatry and Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA
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5
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Jeong DS, Lee JY, Kim MH, Oh JH. Regulation of sexually dimorphic placental adaptation in LPS exposure-induced intrauterine growth restriction. Mol Med 2023; 29:114. [PMID: 37718409 PMCID: PMC10506314 DOI: 10.1186/s10020-023-00688-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 06/15/2023] [Indexed: 09/19/2023] Open
Abstract
BACKGROUND Sexual dimorphism in placental physiology affects the functionality of placental adaptation during adverse pregnancy. Defects of placental function compromise fetal programming, affecting the offspring's adult life. However, studies focusing on the relationship between sex-specific placental adaptation and consequent fetal maldevelopment under sub-optimal uterus milieu are still elusive. METHODS Here, we investigated the effects of maternal lipopolysaccharide (LPS) exposure between placental sex. Pregnant ICR mice received intraperitoneal injection of phosphate-buffered saline or 100, 200, and 400 µg/kg LPS on the gestational day (GD) 15.5. To determine whether prenatal maternal LPS exposure resulted in complicated pregnancy outcomes, survival rate of embryos was calculated and the growth of embryos and placentas was examined. To elucidate global transcriptomic changes occurring in the placenta, total RNA-sequencing (RNA-seq) was performed in female and male placentas. RESULTS LPS administration induced placental inflammation in both sexes at GD 17.5. Prenatal infection resulted in growth retardation in both sexes of embryos, and especially more prevalently in male. Impaired placental development was observed in a sex-specific manner. LPS 400 µg/kg reduced the percentage area of the labyrinth in females and junctional zone in males, respectively. RNA-sequencing revealed widespread sexually dimorphic transcriptional changes in placenta. In particular, representative changes were involved in biological processes such as trophoblast differentiation, nutrient/ion transporter, pregnancy, and immune system. CONCLUSIONS Our results present the sexually dimorphic responses of placental physiology in intrauterine growth restriction model and provide tentative relationship further to be elucidated between sex-biased placental functional change and long-term effects on the offspring's later life.
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Affiliation(s)
- Da Som Jeong
- Department of Anatomy, Embryology Laboratory, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Ji-Yeon Lee
- Vivozon, Inc, Kolon Digital Tower3, 49, Achasan-ro, Seongdong-gu, Seoul, Republic of Korea
| | - Myoung Hee Kim
- Department of Anatomy, Embryology Laboratory, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
| | - Ji Hoon Oh
- Department of Biological Sciences, Keimyung University College of Natural Sciences, Daegu, 42601, Republic of Korea.
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Kajdy A, Sys D, Modzelewski J, Bogusławska J, Cymbaluk-Płoska A, Kwiatkowska E, Bednarek-Jędrzejek M, Borowski D, Stefańska K, Rabijewski M, Baran A, Torbe A, Feduniw S, Kwiatkowski S. Evidence of Placental Aging in Late SGA, Fetal Growth Restriction and Stillbirth-A Systematic Review. Biomedicines 2023; 11:1785. [PMID: 37509425 PMCID: PMC10376283 DOI: 10.3390/biomedicines11071785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/09/2023] [Accepted: 06/15/2023] [Indexed: 07/30/2023] Open
Abstract
During pregnancy, the placenta undergoes a natural aging process, which is considered normal. However, it has been hypothesized that an abnormally accelerated and premature aging of the placenta may contribute to placenta-related health issues. Placental senescence has been linked to several obstetric complications, including abnormal fetal growth, preeclampsia, preterm birth, and stillbirth, with stillbirth being the most challenging. A systematic search was conducted on Pubmed, Embase, and Scopus databases. Twenty-two full-text articles were identified for the final synthesis. Of these, 15 presented original research and 7 presented narrative reviews. There is a paucity of evidence in the literature on the role of placental aging in late small for gestational age (SGA), fetal growth restriction (FGR), and stillbirth. For future research, guidelines for both planning and reporting research must be implemented. The inclusion criteria should include clear differentiation between early and late SGA and FGR. As for stillbirths, only those with no other known cause of stillbirth should be included in the studies. This means excluding stillbirths due to congenital defects, infections, placental abruption, and maternal conditions affecting feto-maternal hemodynamics.
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Affiliation(s)
- Anna Kajdy
- First Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, 01-004 Warsaw, Poland
| | - Dorota Sys
- Department of Medical Statistics, School of Public Health, Centre of Postgraduate Medical Education, 01-828 Warsaw, Poland
| | - Jan Modzelewski
- First Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, 01-004 Warsaw, Poland
| | - Joanna Bogusławska
- Department of Biochemistry and Molecular Biology, Centre of Postgraduate Medical Education, 01-813 Warsaw, Poland
| | - Aneta Cymbaluk-Płoska
- Department of Gynecological Surgery and Gynecological Oncology of Adults and Adolescents, Pomeranian Medical University, 70-111 Szczecin, Poland
| | - Ewa Kwiatkowska
- Department of Nephrology, Transplantology and Internal Medicine, Pomeranian Medical University, 70-111 Szczecin, Poland
| | | | - Dariusz Borowski
- Clinic of Obstetrics and Gynaecology, Provincial Combined Hospital in Kielce, 25-736 Kielce, Poland
| | - Katarzyna Stefańska
- Department of Obstetrics, Medical University of Gdańsk, 80-210 Gdańsk, Poland
| | - Michał Rabijewski
- Department of Reproductive Health, Center of Postgraduate Medical Education, Centre of Postgraduate Medical Education, Żelazna 90 St., 01-004 Warsaw, Poland
| | - Arkadiusz Baran
- First Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, 01-004 Warsaw, Poland
| | - Andrzej Torbe
- Department Obstetrics and Gynecology, Pomeranian Medical University, 70-111 Szczecin, Poland
| | - Stepan Feduniw
- Department of Gynecology, University Hospital Zürich, 8091 Zürich, Switzerland
| | - Sebastian Kwiatkowski
- Department Obstetrics and Gynecology, Pomeranian Medical University, 70-111 Szczecin, Poland
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7
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Rosario FJ, Chopra A, Biggar K, Powell TL, Gupta MB, Jansson T. Placental Remote Control of Fetal Metabolism: Trophoblast mTOR Signaling Regulates Liver IGFBP-1 Phosphorylation and IGF-1 Bioavailability. Int J Mol Sci 2023; 24:7273. [PMID: 37108437 PMCID: PMC10138459 DOI: 10.3390/ijms24087273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/02/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
The mechanisms mediating the restricted growth in intrauterine growth restriction (IUGR) remain to be fully established. Mechanistic target of rapamycin (mTOR) signaling functions as a placental nutrient sensor, indirectly influencing fetal growth by regulating placental function. Increased secretion and the phosphorylation of fetal liver IGFBP-1 are known to markedly decrease the bioavailability of IGF-1, a major fetal growth factor. We hypothesized that an inhibition of trophoblast mTOR increases liver IGFBP-1 secretion and phosphorylation. We collected conditioned media (CM) from cultured primary human trophoblast (PHT) cells with a silenced RAPTOR (specific inhibition of mTOR Complex 1), RICTOR (inhibition of mTOR Complex 2), or DEPTOR (activates both mTOR Complexes). Subsequently, HepG2 cells, a well-established model for human fetal hepatocytes, were cultured in CM from PHT cells, and IGFBP-1 secretion and phosphorylation were determined. CM from PHT cells with either mTORC1 or mTORC2 inhibition caused the marked hyperphosphorylation of IGFBP-1 in HepG2 cells as determined by 2D-immunoblotting while Parallel Reaction Monitoring-Mass Spectrometry (PRM-MS) identified increased dually phosphorylated Ser169 + Ser174. Furthermore, using the same samples, PRM-MS identified multiple CK2 peptides coimmunoprecipitated with IGFBP-1 and greater CK2 autophosphorylation, indicating the activation of CK2, a key enzyme mediating IGFBP-1 phosphorylation. Increased IGFBP-1 phosphorylation inhibited IGF-1 function, as determined by the reduced IGF-1R autophosphorylation. Conversely, CM from PHT cells with mTOR activation decreased IGFBP-1 phosphorylation. CM from non-trophoblast cells with mTORC1 or mTORC2 inhibition had no effect on HepG2 IGFBP-1 phosphorylation. Placental mTOR signaling may regulate fetal growth by the remote control of fetal liver IGFBP-1 phosphorylation.
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Affiliation(s)
- Fredrick J. Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Anand Chopra
- Institute of Biochemistry, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Kyle Biggar
- Institute of Biochemistry, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Theresa L. Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Department of Biochemistry, University of Western Ontario, London, ON N6A 3K7, Canada
| | - Madhulika B. Gupta
- Department of Biochemistry, University of Western Ontario, London, ON N6A 3K7, Canada
- Department of Pediatrics, University of Western Ontario, London, ON N6A 3K7, Canada
- Children’s Health Research Institute, University of Western Ontario, London, ON N6A 3K7, Canada
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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8
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Garcia-Santillan JA, Lazo-de-la-Vega-Monroy ML, Rodriguez-Saldaña GC, Solis-Barbosa MA, Corona-Figueroa MA, Gonzalez-Dominguez MI, Gomez-Zapata HM, Malacara JM, Barbosa-Sabanero G. Placental Nutrient Transporters and Maternal Fatty Acids in SGA, AGA, and LGA Newborns From Mothers With and Without Obesity. Front Cell Dev Biol 2022; 10:822527. [PMID: 35399516 PMCID: PMC8990844 DOI: 10.3389/fcell.2022.822527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 02/25/2022] [Indexed: 12/01/2022] Open
Abstract
Adverse environmental factors in early life result in fetal metabolic programming and increased risk of adult diseases. Birth weight is an indirect marker of the intrauterine environment, modulated by nutrient availability and placental transport capacity. However, studies of placental transporters in idiopathic birth weight alterations and in maternal obesity in relation to neonatal metabolic outcomes are scarce. We aimed to analyze the placental nutrient transporter protein expression in small (SGA, n = 14), adequate (AGA, n = 18), and large (LGA n = 10) gestational age term for newborns from healthy or obese mothers (LGA-OB, n = 9) and their association with maternal fatty acids, metabolic status, placental triglycerides, and neonatal outcomes. The transporter expression was determined by Western blot. The fatty acid profile was evaluated by gas chromatography, and placental triglycerides were quantified by an enzymatic colorimetric method. GLUT1 was higher in LGA and lower in SGA and positively correlated with maternal HbA1c and placental weight (PW). SNAT2 was lower in SGA, while SNAT4 was lower in LGA-OB. FATP1 was lower in SGA and higher in LGA. SNAT4 correlated negatively and FATP1 correlated positively with the PW and birth anthropometry (BA). Placental triglycerides were higher in LGA and LGA-OB and correlated with pregestational BMI, maternal insulin, and BA. Maternal docosahexaenoic acid (DHA) was higher in SGA, specifically in male placentas, correlating negatively with maternal triglycerides, PW, cord glucose, and abdominal perimeter. Palmitic acid (PA) correlated positively with FATP4 and cord insulin, linoleic acid correlated negatively with PA and maternal cholesterol, and arachidonic acid correlated inversely with maternal TG and directly with FATP4. Our study highlights the importance of placental programming in birth weight both in healthy and obese pregnancies.
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Affiliation(s)
| | | | | | - Miguel-Angel Solis-Barbosa
- Medical Sciences Department, Health Sciences Division, University of Guanajuato, Campus Leon, Guanajuato, Mexico
| | | | | | | | - Juan-Manuel Malacara
- Medical Sciences Department, Health Sciences Division, University of Guanajuato, Campus Leon, Guanajuato, Mexico
| | - Gloria Barbosa-Sabanero
- Medical Sciences Department, Health Sciences Division, University of Guanajuato, Campus Leon, Guanajuato, Mexico
- *Correspondence: Gloria Barbosa-Sabanero,
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9
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Aye IL, Aiken CE, Charnock-Jones DS, Smith GC. Placental energy metabolism in health and disease-significance of development and implications for preeclampsia. Am J Obstet Gynecol 2022; 226:S928-S944. [PMID: 33189710 DOI: 10.1016/j.ajog.2020.11.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/02/2020] [Accepted: 11/03/2020] [Indexed: 02/08/2023]
Abstract
The placenta is a highly metabolically active organ fulfilling the bioenergetic and biosynthetic needs to support its own rapid growth and that of the fetus. Placental metabolic dysfunction is a common occurrence in preeclampsia although its causal relationship to the pathophysiology is unclear. At the outset, this may simply be seen as an "engine out of fuel." However, placental metabolism plays a vital role beyond energy production and is linked to physiological and developmental processes. In this review, we discuss the metabolic basis for placental dysfunction and propose that the alterations in energy metabolism may explain many of the placental phenotypes of preeclampsia such as reduced placental and fetal growth, redox imbalance, oxidative stress, altered epigenetic and gene expression profiles, and the functional consequences of these aberrations. We propose that placental metabolic reprogramming reflects the dynamic physiological state allowing the tissue to adapt to developmental changes and respond to preeclampsia stress, whereas the inability to reprogram placental metabolism may result in severe preeclampsia phenotypes. Finally, we discuss common tested and novel therapeutic strategies for treating placental dysfunction in preeclampsia and their impact on placental energy metabolism as possible explanations into their potential benefits or harm.
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10
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Tanaka K, Tanaka H, Tachibana R, Yoshikawa K, Kawamura T, Takakura S, Takeuchi H, Ikeda T. Tadalafil Treatment of Mice with Fetal Growth Restriction and Preeclampsia Improves Placental mTOR Signaling. Int J Mol Sci 2022; 23:ijms23031474. [PMID: 35163395 PMCID: PMC8835936 DOI: 10.3390/ijms23031474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 12/10/2022] Open
Abstract
Fetal growth restriction (FGR) is a major cause of poor perinatal outcomes. Although several studies have been conducted to improve the prognosis of FGR in infants, no effective intrauterine treatment method has been established. This study aimed to use tadalafil, a phosphodiesterase 5 inhibitor (PDE5) inhibitor, as a novel intrauterine treatment and conducted several basic and clinical studies. The study investigated the effects of tadalafil on placental mTOR signaling. Tadalafil was administered to mice with L-NG-nitroarginine methyl ester (L-NAME)-induced FGR and associated preeclampsia (PE). Placental phosphorylated mTOR (p-mTOR) signaling was assessed by fluorescent immunohistochemical staining and Western blotting. The expression of p-mTOR was significantly decreased in mice with FGR on 13 days post coitum (d.p.c.) but recovered to the same level as that of the control on 17 d.p.c. following tadalafil treatment. The results were similar for 4E-binding protein 1 (4E-BP1) and S6 ribosomal (S6R) protein, which act downstream in the mTOR signaling pathway. We demonstrate that the tadalafil treatment of FGR in mice improved placental mTOR signaling to facilitate fetal growth. Our study provides the key mechanistic detail about the mode of action of tadalafil and thus would be helpful for future clinical studies on FGR.
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Affiliation(s)
| | - Hiroaki Tanaka
- Correspondence: ; Tel.: +81-59-232-1111; Fax: +81-59-231-5202
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11
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Hung TH, Wu CP, Chen SF. Differential Changes in Akt and AMPK Phosphorylation Regulating mTOR Activity in the Placentas of Pregnancies Complicated by Fetal Growth Restriction and Gestational Diabetes Mellitus With Large-For-Gestational Age Infants. Front Med (Lausanne) 2021; 8:788969. [PMID: 34938752 PMCID: PMC8685227 DOI: 10.3389/fmed.2021.788969] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 11/18/2021] [Indexed: 01/04/2023] Open
Abstract
Background: Dysregulation of placental mechanistic target of rapamycin (mTOR) activity has been implicated in the pathophysiology of pregnancies complicated by idiopathic fetal growth restriction (FGR) and gestational diabetes mellitus (GDM) with large-for-gestational-age (LGA) infants. However, the underlying mechanisms remain unclear. Methods: We obtained placentas from women with normal pregnancies (n = 11) and pregnancies complicated by FGR (n = 12) or GDM with LGA infants (n = 12) to compare the levels of total and phosphorylated forms of Akt, AMPK, TSC2, and mTOR among the three groups and used primary cytotrophoblast cells isolated from 30 normal term placentas to study the effects of oxygen–glucose deprivation (OGD) and increasing glucose concentrations on the changes of these factors in vitro. Results: Placentas from FGR pregnancies had lower phosphorylated Akt (p-Akt) levels (P < 0.05), higher p-AMPKα levels (P < 0.01), and lower mTOR phosphorylation (P < 0.05) compared to that of normal pregnant women. Conversely, women with GDM and LGA infants had higher p-Akt (P < 0.001), lower p-AMPKα (P < 0.05), and higher p-mTOR levels (P < 0.05) in the placentas than normal pregnant women. Furthermore, primary cytotrophoblast cells subjected to OGD had lower p-Akt and p-mTOR (both P < 0.05) and higher p-AMPKα levels (P < 0.05) than those cultured under standard conditions, but increasing glucose concentrations had opposite effects on the respective levels. Administering compound C, an AMPK inhibitor, did not significantly affect Akt phosphorylation but partially reversed mTOR phosphorylation. Administering LY294002, an Akt inhibitor, decreased p-mTOR levels, but did not change the levels of total and phosphorylated AMPKα. Conclusion: These results suggest that Akt and AMPK are involved in the regulation of trophoblast mTOR activity in the placentas of pregnancies complicated by FGR and GDM with LGA infants.
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Affiliation(s)
- Tai-Ho Hung
- Department of Obstetrics and Gynecology, Taipei Chang Gung Memorial Hospital, Taipei, Taiwan.,Department of Obstetrics and Gynecology, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.,Department of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chung-Pu Wu
- Department of Obstetrics and Gynecology, Taipei Chang Gung Memorial Hospital, Taipei, Taiwan.,Graduate Institute of Biomedical Sciences, Department of Physiology and Pharmacology and Molecular Medicine Research Center, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Szu-Fu Chen
- Department of Physical Medicine and Rehabilitation, Cheng Hsin General Hospital, Taipei, Taiwan
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12
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Rosario FJ, Kelly AC, Gupta MB, Powell TL, Cox L, Jansson T. Mechanistic Target of Rapamycin Complex 2 Regulation of the Primary Human Trophoblast Cell Transcriptome. Front Cell Dev Biol 2021; 9:670980. [PMID: 34805133 PMCID: PMC8599300 DOI: 10.3389/fcell.2021.670980] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 09/23/2021] [Indexed: 01/04/2023] Open
Abstract
Mechanistic Target of Rapamycin Complex 2 (mTORC2) regulates placental amino acid and folate transport. However, the role of mTORC2 in modulating other placental functions is largely unexplored. We used a gene array following the silencing of rictor to identify genes regulated by mTORC2 in primary human trophoblast (PHT) cells. Four hundred and nine genes were differentially expressed; 102 genes were down-regulated and 307 up-regulated. Pathway analyses demonstrated that inhibition of mTORC2 resulted in increased expression of genes encoding for pro-inflammatory IL-6, VEGF-A, leptin, and inflammatory signaling (SAPK/JNK). Furthermore, down-regulated genes were functionally enriched in genes involved in angiogenesis (Osteopontin) and multivitamin transport (SLC5A6). In addition, the protein expression of leptin, VEGFA, IL-6 was increased and negatively correlated to mTORC2 signaling in human placentas collected from pregnancies complicated by intrauterine growth restriction (IUGR). In contrast, the protein expression of Osteopontin and SLC5A6 was decreased and positively correlated to mTORC2 signaling in human IUGR placentas. In conclusion, mTORC2 signaling regulates trophoblast expression of genes involved in inflammation, micronutrient transport, and angiogenesis, representing novel links between mTOR signaling and multiple placental functions necessary for fetal growth and development.
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Affiliation(s)
- Fredrick J Rosario
- Division of Reproductive Sciences, Department of OB/GYN University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Amy Catherine Kelly
- Division of Reproductive Sciences, Department of OB/GYN University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Madhulika B Gupta
- Children's Health Research Institute and Department of Pediatrics and Biochemistry, University of Western Ontario, London, ON, Canada
| | - Theresa L Powell
- Division of Reproductive Sciences, Department of OB/GYN University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Laura Cox
- Section of Molecular Medicine, Department of Internal Medicine, Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of OB/GYN University of Colorado Anschutz Medical Campus, Aurora, CO, United States
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13
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Christians JK. The Placenta's Role in Sexually Dimorphic Fetal Growth Strategies. Reprod Sci 2021; 29:1895-1907. [PMID: 34699045 DOI: 10.1007/s43032-021-00780-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 10/19/2021] [Indexed: 12/27/2022]
Abstract
Fetal sex affects the risk of pregnancy complications and the long-term effects of prenatal environment on health. Some have hypothesized that growth strategies differ between the sexes, whereby males prioritize growth whereas females are more responsive to their environment. This review evaluates the role of the placenta in such strategies, focusing on (1) mechanisms underlying sexual dimorphism in gene expression, (2) the nature and extent of sexual dimorphism in placental gene expression, (3) sexually dimorphic responses to nutrient supply, and (4) sexual dimorphism in morphology and histopathology. The sex chromosomes contribute to sex differences in placental gene expression, and fetal hormones may play a role later in development. Sexually dimorphic placental gene expression may contribute to differences in the prevalence of complications such as preeclampsia, although this link is not clear. Placental responses to nutrient supply frequently show sexual dimorphism, but there is no consistent pattern where one sex is more responsive. There are sex differences in the prevalence of placental histopathologies, and placental changes in pregnancy complications, but also many similarities. Overall, no clear patterns support the hypothesis that females are more responsive to the maternal environment, or that males prioritize growth. While male fetuses are at greater risk of a variety of complications, total prenatal mortality is higher in females, such that males exposed to early insults may be more likely to survive and be observed in studies of adverse outcomes. Going forward, robust statistical approaches to test for sex-dependent effects must be more widely adopted to reduce the incidence of spurious results.
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Affiliation(s)
- Julian K Christians
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada. .,Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada. .,British Columbia Children's Hospital Research Institute, Vancouver, BC, Canada. .,Women's Health Research Institute, BC Women's Hospital and Health Centre, Vancouver, BC, Canada.
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14
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Mechanistic Target of Rapamycin Complex 1 Signaling Links Hypoxia to Increased IGFBP-1 Phosphorylation in Primary Human Decidualized Endometrial Stromal Cells. Biomolecules 2021; 11:biom11091382. [PMID: 34572595 PMCID: PMC8471256 DOI: 10.3390/biom11091382] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/09/2021] [Accepted: 09/12/2021] [Indexed: 01/01/2023] Open
Abstract
Insulin-like growth factor-1 (IGF-1) bioavailability in pregnancy is governed by IGF binding protein (IGFBP-1) and its phosphorylation, which enhances the affinity of IGFBP-1 for the growth factor. The decidua is the predominant source of maternal IGFBP-1; however, the mechanisms regulating decidual IGFBP-1 secretion/phosphorylation are poorly understood. Using decidualized primary human endometrial stromal cells (HESCs) from first-trimester placenta, we tested the hypothesis that mTORC1 signaling mechanistically links hypoxia to decidual IGFBP-1 secretion/phosphorylation. Hypoxia inhibited mechanistic target of rapamycin (mTORC1) (p-P70-S6K/Thr389, -47%, p = 0.038; p-4E-BP1/Thr70, -55%, p = 0.012) and increased IGFBP-1 (total, +35%, p = 0.005; phosphorylated, Ser101/+82%, p = 0.018; Ser119/+88%, p = 0.039; Ser 169/+157%, p = 0.019). Targeted parallel reaction monitoring-mass spectrometry (PRM-MS) additionally demonstrated markedly increased dual IGFBP-1 phosphorylation (pSer98+Ser101; pSer169+Ser174) in hypoxia. IGFBP-1 hyperphosphorylation inhibited IGF-1 receptor autophosphorylation/ Tyr1135 (-29%, p = 0.002). Furthermore, silencing of tuberous sclerosis complex 2 (TSC2) activated mTORC1 (p-P70-S6K/Thr389, +68%, p = 0.038; p-4E-BP1/Thr70, +30%, p = 0.002) and reduced total/site-specific IGFBP-1 phosphorylation. Importantly, TSC2 siRNA prevented inhibition of mTORC1 and the increase in secretion/site-specific IGFBP-1 phosphorylation in hypoxia. PRM-MS indicated concomitant changes in protein kinase autophosphorylation (CK2/Tyr182; PKC/Thr497; PKC/Ser657). Overall, mTORC1 signaling mechanistically links hypoxia to IGFBP-1 secretion/phosphorylation in primary HESC, implicating decidual mTORC1 inhibition as a novel mechanism linking uteroplacental hypoxia to fetal growth restriction.
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15
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Placenta-specific Slc38a2/SNAT2 knockdown causes fetal growth restriction in mice. Clin Sci (Lond) 2021; 135:2049-2066. [PMID: 34406367 PMCID: PMC8410983 DOI: 10.1042/cs20210575] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 08/12/2021] [Accepted: 08/18/2021] [Indexed: 12/30/2022]
Abstract
Fetal growth restriction (FGR) is a complication of pregnancy that reduces birth weight, markedly increases infant mortality and morbidity and is associated with later-life cardiometabolic disease. No specific treatment is available for FGR. Placentas of human FGR infants have low abundance of sodium-coupled neutral amino acid transporter 2 (Slc38a2/SNAT2), which supplies the fetus with amino acids required for growth. We determined the mechanistic role of placental Slc38a2/SNAT2 deficiency in the development of restricted fetal growth, hypothesizing that placenta-specific Slc38a2 knockdown causes FGR in mice. Using lentiviral transduction of blastocysts with a small hairpin RNA (shRNA), we achieved 59% knockdown of placental Slc38a2, without altering fetal Slc38a2 expression. Placenta-specific Slc38a2 knockdown reduced near-term fetal and placental weight, fetal viability, trophoblast plasma membrane (TPM) SNAT2 protein abundance, and both absolute and weight-specific placental uptake of the amino acid transport System A tracer, 14C-methylaminoisobutyric acid (MeAIB). We also measured human placental SLC38A2 gene expression in a well-defined term clinical cohort and found that SLC38A2 expression was decreased in late-onset, but not early-onset FGR, compared with appropriate for gestational age (AGA) control placentas. The results demonstrate that low placental Slc38a2/SNAT2 causes FGR and could be a target for clinical therapies for late-onset FGR.
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16
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Reduction of In Vivo Placental Amino Acid Transport Precedes the Development of Intrauterine Growth Restriction in the Non-Human Primate. Nutrients 2021; 13:nu13082892. [PMID: 34445051 PMCID: PMC8401823 DOI: 10.3390/nu13082892] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/12/2021] [Accepted: 08/19/2021] [Indexed: 11/17/2022] Open
Abstract
Intrauterine growth restriction (IUGR) is associated with reduced placental amino acid transport (AAT). However, it remains to be established if changes in AAT contribute to restricted fetal growth. We hypothesized that reduced in vivo placental AAT precedes the development of IUGR in baboons with maternal nutrient restriction (MNR). Baboons were fed either a control (ad libitum) or MNR diet (70% of control diet) from gestational day (GD) 30. At GD 140, in vivo transplacental AA transport was measured by infusing nine (13)C- or (2)H-labeled essential amino acids (EAAs) as a bolus into the maternal circulation at cesarean section. A fetal vein-to-maternal artery mole percent excess ratio for each EAA was measured. Microvillous plasma membrane (MVM) system A and system L transport activity were determined. Fetal and placental weights were not significantly different between MNR and control. In vivo, the fetal vein-to-maternal artery mole percent excess ratio was significantly decreased for tryptophan in MNR. MVM system A and system L activity was markedly reduced in MNR. Reduction of in vivo placental amino acid transport precedes fetal growth restriction in the non-human primate, suggesting that reduced placental amino acid transfer may contribute to IUGR.
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17
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Song L, Yan J, Wang N, Wei X, Luo X, Meng K, Sun B. Prenatal exercise reverses high-fat-diet-induced placental alterations and alters male fetal hypothalamus during late gestation in rats†. Biol Reprod 2021; 102:705-716. [PMID: 31742332 DOI: 10.1093/biolre/ioz213] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 10/14/2019] [Accepted: 11/12/2019] [Indexed: 02/06/2023] Open
Abstract
Maternal high-fat (HF) diet negatively affects maternal metabolism and placental function. This study aimed to determine whether gestational exercise prevents the effect of HF diet on placental amino acid transporter expression and nutrient-sensing signaling and the fetal response. Pregnant Sprague-Dawley rats were either fed with a CHOW (13.5% fat) or HF (60% fat) diet during gestation and further divided into two subgroups: voluntary exercised and sedentary. Placentae were collected on gestational day (GD) 14 and GD20, and male placentae were used in this study. We found that gestational exercise ameliorated the detrimental effects of HF diet on dams' adiposity, plasma leptin, and insulin concentrations. Maternal exercise did not influence fetoplacental growth but affected male fetal hypothalamic Leprb, Stat3, Insr, Agrp, and Pomc expressions on GD20. Maternal HF diet decreased placental labyrinth thickness and increased system A amino acid transporter SNAT2 expression, while these changes were normalized by exercise. The activation of placental mechanistic target of rapamycin complex 1/4E-BP1 and LepRb/STAT3 signaling might contribute to the increased placental SNAT2 expression in HF-fed dams, which were reversed by exercise on GD20. These data highlight that gestational exercise reverses HF-diet-induced placental alterations during late gestation without influencing fetal growth. However, maternal exercise altered fetal hypothalamic gene expression, which may affect long-term offspring health.
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Affiliation(s)
- Lin Song
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.,Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Jianqun Yan
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.,Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Nan Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Xiaojing Wei
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.,Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Xiao Luo
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.,Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Kai Meng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.,Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Bo Sun
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.,Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi'an Jiaotong University, Xi'an, Shaanxi, China
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18
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Roeca C, Silva E, Barentsen C, Powell TL, Jansson T. Effects of vitrification and the superovulated environment on placental function and fetal growth in an IVF mouse model. Mol Hum Reprod 2021; 26:624-635. [PMID: 32618997 DOI: 10.1093/molehr/gaaa047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/08/2020] [Indexed: 01/15/2023] Open
Abstract
In studies of human IVF, as compared to frozen embryo transfer (ET), fresh ET is associated with smaller infants and higher risk of small for gestational age infants. Recent observations suggest that ET using vitrified embryos is associated with higher pregnancy and live birth rates compared to fresh ET, but increased rates of large for gestational age infants. The mechanisms underlying these associations are largely unknown, and available evidence suggests that the influence of IVF, vitrification and the superovulated (SO) uterine environment on placental function and fetal growth is complex. This warrants further investigation given the prevalent practice in human IVF of both fresh ET into a SO uterine environment, and vitrification with ET into a more physiologic uterine environment. Using a mouse model that closely resembles human IVF, we investigated if vitrification of IVF embryos better preserves placental function and results in better pregnancy outcomes as compared to fresh ET because of transfer into a more physiologic endometrium. We found that the SO environment, independent of vitrification status, reduced implantation rates, inhibited placental mechanistic target of rapamycin signaling and induced placental stress signaling, resulting in fetal growth restriction (1.080 ± 0.05 g estrous fresh (n = 17 litters), 1.176 ± 0.05 g estrous vitrified (n = 12), 0.771 ± 0.06 g SO fresh (n = 15), 0.895 ± 0.08 g SO vitrified (n = 10), P < 0.0001). In addition, our study suggests that vitrification impairs the developmental potential of IVF blastocysts that resulted in a significantly smaller litter size (2.6 ± 2.3 fresh estrous vs 2.5 ± 2.4 fresh SO vs 1.6 ± 1.7 estrous vitrified vs 1.7 ± 1.8 SO vitrified, P = 0.019), with no effect on fetal growth or placental function at term. Our findings suggest that vitrification may negatively impact early embryonic viability, while the SO maternal uterine environment impairs both placental development and fetal growth in IVF.
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Affiliation(s)
- C Roeca
- Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - E Silva
- Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - C Barentsen
- Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - T L Powell
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - T Jansson
- Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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19
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Akhaphong B, Baumann DC, Beetch M, Lockridge AD, Jo S, Wong A, Zemanovic T, Mohan R, Fondevilla DL, Sia M, Pineda-Cortel MRB, Alejandro EU. Placental mTOR complex 1 regulates fetal programming of obesity and insulin resistance in mice. JCI Insight 2021; 6:149271. [PMID: 34032632 PMCID: PMC8410096 DOI: 10.1172/jci.insight.149271] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 05/19/2021] [Indexed: 11/17/2022] Open
Abstract
Fetal growth restriction, or low birth weight, is a strong determinant for eventual obesity and type 2 diabetes. Clinical studies suggest placental mechanistic target of rapamycin (mTOR) signaling regulates fetal birth weight and the metabolic health trajectory of the offspring. In the current study, we used a genetic model with loss of placental mTOR function (mTOR-KOPlacenta) to test the direct role of mTOR signaling on birth weight and metabolic health in the adult offspring. mTOR-KOPlacenta animals displayed reduced placental area and total weight, as well as fetal body weight at embryonic day (E) 17.5. Birth weight and serum insulin levels were reduced; however, β cell mass was normal in mTOR-KOPlacenta newborns. Adult mTOR-KOPlacenta offspring, under a metabolic high-fat challenge, displayed exacerbated obesity and metabolic dysfunction compared with littermate controls. Subsequently, we tested whether enhancing placental mTOR complex 1 (mTORC1) signaling, via genetic ablation of TSC2, in utero would improve glucose homeostasis in the offspring. Indeed, increased placental mTORC1 conferred protection from diet-induced obesity in the offspring. In conclusion, placental mTORC1 serves as a mechanistic link between placental function and programming of obesity and insulin resistance in the adult offspring.
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Affiliation(s)
- Brian Akhaphong
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Daniel C Baumann
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Megan Beetch
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Amber D Lockridge
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Seokwon Jo
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Alicia Wong
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Tate Zemanovic
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Ramkumar Mohan
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Danica L Fondevilla
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Michelle Sia
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Maria Ruth B Pineda-Cortel
- Research Center for the Natural and Applied Sciences and.,Department of Medical Technology, University of Santo Tomas, Manila, Philippines
| | - Emilyn U Alejandro
- Department of Integrative Biology & Physiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
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20
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Abstract
Almost 2 billion adults in the world are overweight, and more than half of them are classified as obese, while nearly one-third of children globally experience poor growth and development. Given the vast amount of knowledge that has been gleaned from decades of research on growth and development, a number of questions remain as to why the world is now in the midst of a global epidemic of obesity accompanied by the "double burden of malnutrition," where overweight coexists with underweight and micronutrient deficiencies. This challenge to the human condition can be attributed to nutritional and environmental exposures during pregnancy that may program a fetus to have a higher risk of chronic diseases in adulthood. To explore this concept, frequently called the developmental origins of health and disease (DOHaD), this review considers a host of factors and physiological mechanisms that drive a fetus or child toward a higher risk of obesity, fatty liver disease, hypertension, and/or type 2 diabetes (T2D). To that end, this review explores the epidemiology of DOHaD with discussions focused on adaptations to human energetics, placental development, dysmetabolism, and key environmental exposures that act to promote chronic diseases in adulthood. These areas are complementary and additive in understanding how providing the best conditions for optimal growth can create the best possible conditions for lifelong health. Moreover, understanding both physiological as well as epigenetic and molecular mechanisms for DOHaD is vital to most fully address the global issues of obesity and other chronic diseases.
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Affiliation(s)
- Daniel J Hoffman
- Department of Nutritional Sciences, Program in International Nutrition, and Center for Childhood Nutrition Research, New Jersey Institute for Food, Nutrition, and Health, Rutgers, the State University of New Jersey, New Brunswick, New Jersey
| | - Theresa L Powell
- Department of Pediatrics and Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Emily S Barrett
- Department of Biostatistics and Epidemiology, School of Public Health and Division of Exposure Science and Epidemiology, Rutgers Environmental and Occupational Health Sciences Institute, Rutgers, the State University of New Jersey, New Brunswick, New Jersey
| | - Daniel B Hardy
- Department of Biostatistics and Epidemiology, School of Public Health and Division of Exposure Science and Epidemiology, Rutgers Environmental and Occupational Health Sciences Institute, Rutgers, the State University of New Jersey, New Brunswick, New Jersey
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21
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Cilvik SN, Wesolowski SR, Anthony RV, Brown LD, Rozance PJ. Late gestation fetal hyperglucagonaemia impairs placental function and results in diminished fetal protein accretion and decreased fetal growth. J Physiol 2021; 599:3403-3427. [PMID: 33878802 DOI: 10.1113/jp281288] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 04/06/2021] [Indexed: 12/14/2022] Open
Abstract
KEY POINTS Fetal glucagon concentrations are elevated in the setting of placental insufficiency, hypoxia and elevated stress hormones. Chronically elevated glucagon concentrations in the adult result in profound decreases in amino acid concentrations and lean body mass. Experimental elevation of fetal glucagon concentrations in a late-gestation pregnant sheep results in lower fetal amino acid concentrations, lower protein accretion and lower fetal weight, in addition to decreased placental function. This study demonstrates a negative effect of glucagon on fetal protein accretion and growth, and also provides the first example of a fetal hormone that negatively regulates placental nutrient transport and blood flow. ABSTRACT Fetal glucagon concentrations are elevated in the setting of placental insufficiency and fetal stress. Postnatal studies have demonstrated the importance of glucagon in amino acid metabolism, and limited fetal studies have suggested that glucagon inhibits umbilical uptake of certain amino acids. We hypothesized that chronic fetal hyperglucagonaemia would decrease amino acid transfer and increase amino acid oxidation by the fetus. Late gestation singleton fetal sheep received a direct intravenous infusion of glucagon (GCG; 5 or 50 ng/kg/min; n = 7 and 5, respectively) or a vehicle control (n = 10) for 8-10 days. Fetal and maternal nutrient concentrations, uterine and umbilical blood flows, fetal leucine flux, nutrient uptake rates, placental secretion of chorionic somatomammotropin (CSH), and targeted placental gene expression were measured. GCG fetuses had 13% lower fetal weight compared to controls (P = 0.0239) and >28% lower concentrations of 16 out of 21 amino acids (P < 0.02). Additionally, protein synthesis was 49% lower (P = 0.0005), and protein accretion was 92% lower in GCG fetuses (P = 0.0006). Uterine blood flow was 33% lower in ewes with GCG fetuses (P = 0.0154), while umbilical blood flow was similar. Fetal hyperglucagonaemia lowered uterine uptake of 10 amino acids by >48% (P < 0.05) and umbilical uptake of seven amino acids by >29% (P < 0.04). Placental secretion of CSH into maternal circulation was reduced by 80% compared to controls (P = 0.0080). This study demonstrates a negative effect of glucagon on fetal protein accretion and growth. It also demonstrates that glucagon, a hormone of fetal origin, negatively regulates maternal placental nutrient transport function, placental CSH production and uterine blood flow.
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Affiliation(s)
- Sarah N Cilvik
- Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | | | - Russ V Anthony
- Colorado State University College of Veterinary Medicine, Fort Collins, CO, USA
| | - Laura D Brown
- University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Paul J Rozance
- University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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22
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Rosario FJ, Powell TL, Gupta MB, Cox L, Jansson T. mTORC1 Transcriptional Regulation of Ribosome Subunits, Protein Synthesis, and Molecular Transport in Primary Human Trophoblast Cells. Front Cell Dev Biol 2020; 8:583801. [PMID: 33324640 PMCID: PMC7726231 DOI: 10.3389/fcell.2020.583801] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 10/20/2020] [Indexed: 12/12/2022] Open
Abstract
Mechanistic Target of Rapamycin Complex 1 (mTORC1) serves as positive regulator of placental nutrient transport and mitochondrial respiration. The role of mTORC1 signaling in modulating other placental functions is largely unexplored. We used gene array following silencing of raptor to identify genes regulated by mTORC1 in primary human trophoblast (PHT) cells. Seven hundred and thirty-nine genes were differentially expressed; 487 genes were down-regulated and 252 up-regulated. Bioinformatic analyses demonstrated that inhibition of mTORC1 resulted in decreased expression of genes encoding ribosomal proteins in the 60S and 40S ribosome subunits. Furthermore, down-regulated genes were functionally enriched in genes involved in eIF2, sirtuin and mTOR signaling, mitochondrial function, and glutamine and zinc transport. Stress response genes were enriched among up-regulated genes following mTORC1 inhibition. The protein expression of ribosomal proteins RPL26 (RPL26) and Ribosomal Protein S10 (RPS10) was decreased and positively correlated to mTORC1 signaling and System A amino acid transport in human placentas collected from pregnancies complicated by intrauterine growth restriction (IUGR). In conclusion, mTORC1 signaling regulates the expression of trophoblast genes involved in ribosome and protein synthesis, mitochondrial function, lipid metabolism, nutrient transport, and angiogenesis, representing novel links between mTOR signaling and multiple placental functions critical for normal fetal growth and development.
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Affiliation(s)
- Fredrick J. Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Theresa L. Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Madhulika B. Gupta
- Department of Biochemistry, University of Western Ontario, London, ON, Canada
| | - Laura Cox
- Center for Precision Medicine, Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
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23
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Keleher MR, Erickson K, Kechris K, Yang IV, Dabelea D, Friedman JE, Boyle KE, Jansson T. Associations between the activity of placental nutrient-sensing pathways and neonatal and postnatal metabolic health: the ECHO Healthy Start cohort. Int J Obes (Lond) 2020; 44:2203-2212. [PMID: 32327723 PMCID: PMC8329931 DOI: 10.1038/s41366-020-0574-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 03/10/2020] [Accepted: 03/27/2020] [Indexed: 12/28/2022]
Abstract
OBJECTIVE Our hypothesis was that the activity of placental nutrient-sensing pathways is associated with adiposity and metabolic health in childhood. RESEARCH DESIGN AND METHODS Using placental villus samples from healthy mothers from the Healthy Start Study, we measured the abundance and phosphorylation of key intermediates in the mTOR, insulin, AMPK, and ER stress signaling pathways. Using multivariate multiple regression models, we tested the association between placental proteins and offspring adiposity (%fat mass) at birth (n = 109), 4-6 months (n = 104), and 4-6 years old (n = 64), adjusted for offspring sex and age. RESULTS Placental mTORC1 phosphorylation was positively associated with adiposity at birth (R2 = 0.13, P = 0.009) and 4-6 years (R2 = 0.15, P = 0.046). The mTORC2 target PKCα was positively associated with systolic blood pressure at 4-6 years (β = 2.90, P = 0.005). AMPK phosphorylation was positively associated with adiposity at birth (β = 2.32, P = 0.023), but the ratio of phosphorylated to total AMPK was negatively associated with skinfold thickness (β = -2.37, P = 0.022) and body weight (β = -2.92, P = 0.005) at 4-6 years. CONCLUSIONS This is the first report of associations between key placental protein activity measures and longitudinal child outcomes at various life stages. Our data indicate that AMPK and mTOR signaling are linked to cardiometabolic measures at birth and 4-6 years, providing novel insight into potential mechanisms underpinning how metabolic signaling in the placenta is associated with future risk of cardiovascular disease.
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Affiliation(s)
- Madeline Rose Keleher
- Section of Nutrition, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
- The Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, Aurora, CO, USA.
| | - Kathryn Erickson
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Katerina Kechris
- The Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, Aurora, CO, USA
- Department of Biostatistics & Informatics, Colorado School of Public Health, Aurora, CO, USA
| | - Ivana V Yang
- The Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, Aurora, CO, USA
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Dana Dabelea
- The Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, Aurora, CO, USA
- Department of Epidemiology, Colorado School of Public Health, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Jacob E Friedman
- Department of Pediatrics, Section of Neonatology, University of Colorado School of Medicine, Aurora, CO, USA
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Kristen E Boyle
- Section of Nutrition, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- The Lifecourse Epidemiology of Adiposity and Diabetes (LEAD) Center, Aurora, CO, USA
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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24
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McIntyre KR, Vincent KMM, Hayward CE, Li X, Sibley CP, Desforges M, Greenwood SL, Dilworth MR. Human placental uptake of glutamine and glutamate is reduced in fetal growth restriction. Sci Rep 2020; 10:16197. [PMID: 33004923 PMCID: PMC7530652 DOI: 10.1038/s41598-020-72930-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 09/02/2020] [Indexed: 12/21/2022] Open
Abstract
Fetal growth restriction (FGR) is a significant risk factor for stillbirth, neonatal complications and adulthood morbidity. Compared with those of appropriate weight for gestational age (AGA), FGR babies have smaller placentas with reduced activity of amino acid transporter systems A and L, thought to contribute to poor fetal growth. The amino acids glutamine and glutamate are essential for normal placental function and fetal development; whether transport of these is altered in FGR is unknown. We hypothesised that FGR is associated with reduced placental glutamine and glutamate transporter activity and expression, and propose the mammalian target of rapamycin (mTOR) signaling pathway as a candidate mechanism. FGR infants [individualised birth weight ratio (IBR) < 5th centile] had lighter placentas, reduced initial rate uptake of 14C-glutamine and 14C-glutamate (per mg placental protein) but higher expression of key transporter proteins (glutamine: LAT1, LAT2, SNAT5, glutamate: EAAT1) versus AGA [IBR 20th-80th]. In further experiments, in vitro exposure to rapamycin inhibited placental glutamine and glutamate uptake (24 h, uncomplicated pregnancies) indicating a role of mTOR in regulating placental transport of these amino acids. These data support our hypothesis and suggest that abnormal glutamine and glutamate transporter activity is part of the spectrum of placental dysfunction in FGR.
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Affiliation(s)
- Kirsty R McIntyre
- Maternal and Fetal Health Research Centre, Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK. .,Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK. .,School of Medicine, Dentistry and Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Wolfson Medical School Building, University Avenue, Glasgow, G12 8QQ, UK.
| | - Kirsty M M Vincent
- Maternal and Fetal Health Research Centre, Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.,Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Christina E Hayward
- Maternal and Fetal Health Research Centre, Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.,Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Xiaojia Li
- Maternal and Fetal Health Research Centre, Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.,Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Colin P Sibley
- Maternal and Fetal Health Research Centre, Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.,Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Michelle Desforges
- Maternal and Fetal Health Research Centre, Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.,Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Susan L Greenwood
- Maternal and Fetal Health Research Centre, Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.,Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Mark R Dilworth
- Maternal and Fetal Health Research Centre, Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.,Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
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25
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Chen YH, Liu ZB, Ma L, Zhang ZC, Fu L, Yu Z, Chen W, Song YP, Wang P, Wang H, Xu DX. Gestational vitamin D deficiency causes placental insufficiency and fetal intrauterine growth restriction partially through inducing placental inflammation. J Steroid Biochem Mol Biol 2020; 203:105733. [PMID: 32784046 DOI: 10.1016/j.jsbmb.2020.105733] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/24/2020] [Accepted: 07/27/2020] [Indexed: 12/13/2022]
Abstract
Several epidemiological studies suggest an association between vitamin D deficiency (VDD) and fetal intrauterine growth restriction (IUGR). Here, we explored the mechanism through which VDD induced fetal IUGR. Pregnant mice were fed with VDD diet to establish VDD model. Cyp27b1+/- mice were generated to develop a model of active vitamin D3 deficiency. Cyp27b1+/- mice were injected with either 1α,25(OH)2D3 or vehicle once a day throughout pregnancy. As expected, fetal weight and crown-rump length were reduced in VDD diet-fed mice. Correspondingly, fetal weight and crown-rump length were lower in cyp27b1+/- mice. 1α,25(OH)2D3 elevated fetal weight and crown-rump length, and protected cyp27b1+/- mice from fetal IUGR. Further analysis found that placental proliferation was inhibited and placental weight was decreased in VDD diet-fed mice. Several growth factors and nutrient transfer pumps were downregulated in the placentas of VDD diet-fed mice. Mechanistically, several inflammatory cytokines were upregulated and placental NF-κB was activated not only in VDD diet-fed mice but also in VDD pregnant women. Interestingly, 1α,25(OH)2D3 inhibited the downregulated of placental nutrient transfer pumps and the upregulated of placental inflammatory cytokines in Cyp27b1+/- mice. These results provide experimental evidence that gestational VDD causes placental insufficiency and fetal IUGR may be through inducing placental inflammation.
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Affiliation(s)
- Yuan Hua Chen
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China; Department of Histology and Embryology, Anhui Medical University, Hefei, 230032, China
| | - Zhi Bing Liu
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China
| | - Li Ma
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China
| | - Zhi Cheng Zhang
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China
| | - Lin Fu
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China
| | - Zhen Yu
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China
| | - Wei Chen
- Department of Histology and Embryology, Anhui Medical University, Hefei, 230032, China
| | - Ya Ping Song
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China
| | - Peng Wang
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China
| | - Hua Wang
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China
| | - De Xiang Xu
- Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Department of Toxicology, Anhui Medical University, Hefei, 230032, China.
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26
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Abnormalities of placental development and function are associated with the different fetal growth patterns of hypoplastic left heart syndrome and transposition of the great arteries. Placenta 2020; 101:57-65. [PMID: 32927345 DOI: 10.1016/j.placenta.2020.09.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 08/31/2020] [Accepted: 09/03/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Birthweight is a critical predictor of congenital heart disease (CHD) surgical outcomes. Hypoplastic left heart syndrome (HLHS) is cyanotic CHD with known fetal growth restriction and placental abnormalities. Transposition of the great arteries (TGA) is cyanotic CHD with normal fetal growth. Comparison of the placenta in these diagnoses may provide insights on the fetal growth abnormality of CHD. METHODS Clinical data and placental histology from placentas associated with Transposition of the Great Arteries (TGA) were analyzed for gross pathology, morphology, maturity and vascularity and compared to both control and previously analyzed HLHS placentas [1]. RNA was isolated from HLHS, TGA and control placentas and sequenced by Illumina HiSeq.Transcriptome analysis was performed using AltAnalyze. Immunohistochemistry was utilized to assess placental nutrient transporter expression in all three groups. RESULTS Placental weight was reduced in TGA cases, and demonstrated reduced villous vasculature, immature terminal villi in the parenchyma compared to controls and reflected our previous data from HLHS placentas. However, birth weight was not reduced in TGA cases compared to controls in contrast to the HLHS cohort and birthweight:placental weight ratio was significantly increased in TGA cases but not HLHS compared to control. Transcriptomic and histologic analysis demonstrates reduced cell activity and nutrient transport capability in HLHS but not TGA placentas which appear to increase/maintain these mechanisms. CONCLUSIONS Despite common vascular disturbances in placentas from HLHAs and TGA, these do not account for the disparities in birthweights frequently seen between these CHD subtypes, in contrast our transcriptomic and histologic analyses reveal differentially regulated mechanisms between the subtypes that may explain these disparities.
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27
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Down-regulation of placental Cdc42 and Rac1 links mTORC2 inhibition to decreased trophoblast amino acid transport in human intrauterine growth restriction. Clin Sci (Lond) 2020; 134:53-70. [PMID: 31825077 DOI: 10.1042/cs20190794] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 11/26/2019] [Accepted: 12/11/2019] [Indexed: 12/31/2022]
Abstract
Intrauterine growth restriction (IUGR) increases the risk for perinatal complications and metabolic and cardiovascular disease later in life. The syncytiotrophoblast (ST) is the transporting epithelium of the human placenta, and decreased expression of amino acid transporter isoforms in the ST plasma membranes is believed to contribute to IUGR. Placental mechanistic target of rapamycin Complex 2 (mTORC2) signaling is inhibited in IUGR and regulates the trafficking of key amino acid transporter (AAT) isoforms to the ST plasma membrane; however, the molecular mechanisms are unknown. Cdc42 and Rac1 are Rho-GTPases that regulate actin-binding proteins, thereby modulating the structure and dynamics of the actin cytoskeleton. We hypothesized that inhibition of mTORC2 decreases AAT expression in the plasma membrane and amino acid uptake in primary human trophoblast (PHT) cells mediated by down-regulation of Cdc42 and Rac1. mTORC2, but not mTORC1, inhibition decreased the Cdc42 and Rac1 expression. Silencing of Cdc42 and Rac1 inhibited the activity of the System L and A transporters and markedly decreased the trafficking of LAT1 (System L isoform) and SNAT2 (System A isoform) to the plasma membrane. mTORC2 inhibition by silencing of rictor failed to decrease AAT following activation of Cdc42/Rac1. Placental Cdc42 and Rac1 protein expression was down-regulated in human IUGR and was positively correlated with placental mTORC2 signaling. In conclusion, mTORC2 regulates AAT trafficking in PHT cells by modulating Cdc42 and Rac1. Placental mTORC2 inhibition in human IUGR may contribute to decreased placental amino acid transfer and reduced fetal growth mediated by down-regulation of Cdc42 and Rac1.
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28
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Dong J, Shin N, Chen S, Lei J, Burd I, Wang X. Is there a definite relationship between placental mTOR signaling and fetal growth? Biol Reprod 2020; 103:471-486. [PMID: 32401303 DOI: 10.1093/biolre/ioaa070] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/22/2020] [Accepted: 05/11/2020] [Indexed: 02/07/2023] Open
Abstract
Fetal growth restriction and overgrowth are common obstetrical complications that result in adverse perinatal outcomes and long-term health risks later in life, including neurodevelopmental dysfunction and adult metabolic syndrome. The placenta plays a critical role in the nutrition transfer from mother to fetus and even exerts adaptive mechanism when the fetus is under poor developmental conditions. The mammalian/mechanistic target of rapamycin (mTOR) signaling serves as a critical hub of cell growth, survival, and metabolism in response to nutrients, growth factors, energy, and stress signals. Placental mTOR signaling regulates placental function, including oxygen and nutrient transport. Therefore, placental mTOR signaling is hypothesized to have a positive relationship with fetal growth. In this review, we summarize that most studies support the current evidence that there is connection between placental mTOR signaling and abnormal fetal growth; however, but more studies should be performed following a vigorous and unanimous method for assessment to determine placental mTOR activity.
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Affiliation(s)
- Jie Dong
- Reproductive Medical Center, Department of Gynecology and Obstetrics, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Na Shin
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Shuqiang Chen
- Reproductive Medical Center, Department of Gynecology and Obstetrics, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Jun Lei
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Irina Burd
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xiaohong Wang
- Reproductive Medical Center, Department of Gynecology and Obstetrics, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi Province, China
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29
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Comparative Study of PPAR γ Targets in Human Extravillous and Villous Cytotrophoblasts. PPAR Res 2020; 2020:9210748. [PMID: 32308672 PMCID: PMC7152979 DOI: 10.1155/2020/9210748] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/26/2020] [Accepted: 02/11/2020] [Indexed: 12/15/2022] Open
Abstract
Trophoblasts, as the cells that make up the main part of the placenta, undergo cell differentiation processes such as invasion, migration, and fusion. Abnormalities in these processes can lead to a series of gestational diseases whose underlying mechanisms are still unclear. One protein that has proven to be essential in placentation is the peroxisome proliferator-activated receptor γ (PPARγ), which is expressed in the nuclei of extravillous cytotrophoblasts (EVCTs) in the first trimester and villous cytotrophoblasts (VCTs) throughout pregnancy. Here, we aimed to explore the genome-wide effects of PPARγ on EVCTs and VCTs via treatment with the PPARγ-agonist rosiglitazone. EVCTs and VCTs were purified from human chorionic villi, cultured in vitro, and treated with rosiglitazone. The transcriptomes of both types of cells were then quantified using microarray profiling. Differentially expressed genes (DEGs) were filtered and submitted for gene ontology (GO) annotation and pathway analysis with ClueGO. The online tool STRING was used to predict PPARγ and DEG protein interactions, while iRegulon was used to predict the binding sites for PPARγ and DEG promoters. GO and pathway terms were compared between EVCTs and VCTs with clusterProfiler. Visualizations were prepared in Cytoscape. From our microarray data, 139 DEGs were detected in rosiglitazone-treated EVCTs (RT-EVCTs) and 197 DEGs in rosiglitazone-treated VCTs (RT-VCTs). Downstream annotation analysis revealed the similarities and differences between RT-EVCTs and RT-VCTs with respect to the biological processes, molecular functions, cellular components, and KEGG pathways affected by the treatment, as well as predicted binding sites for both protein-protein interactions and transcription factor-target gene interactions. These results provide a broad perspective of PPARγ-activated processes in trophoblasts; further analysis of the transcriptomic signatures of RT-EVCTs and RT-VCTs should open new avenues for future research and contribute to the discovery of possible drug-targeted genes or pathways in the human placenta.
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30
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Howell KR, Law AJ. Neurodevelopmental concepts of schizophrenia in the genome-wide association era: AKT/mTOR signaling as a pathological mediator of genetic and environmental programming during development. Schizophr Res 2020; 217:95-104. [PMID: 31522868 PMCID: PMC7065975 DOI: 10.1016/j.schres.2019.08.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 08/28/2019] [Accepted: 08/31/2019] [Indexed: 12/14/2022]
Abstract
Normative brain development is contingent on the complex interplay between genes and environment. Schizophrenia (SCZ) is considered a highly polygenic, neurodevelopmental disorder associated with impaired neural circuit development, neurocognitive function and variations in neurotransmitter signaling systems, including dopamine. Significant evidence, accumulated over the last 30 years indicates a role for the in utero environment in SCZ pathophysiology. Emerging data suggests that changes in placental programming and function may mediate the link between genetic risk, early life complications (ELC) and adverse neurodevelopmental outcomes, with risk highlighted in key developmental drivers that converge on AKT/mTOR signaling. In this article we overview select risk genes identified through recent genome-wide association studies of SCZ including AKT3, miR-137, DRD2, and AKT1 itself. We propose that through convergence on AKT/mTOR signaling, these genes are critical factors directing both placentation and neurodevelopment, influencing risk for SCZ through dysregulation of placental function, metabolism and early brain development. We discuss association of risk genes in the context of their known roles in neurodevelopment, placental expression and their possible mechanistic links to SCZ in the broad context of the 'developmental origins of adult disease' construct. Understanding how common genetic variation impacts early fetal programming may advance our knowledge of disease etiology and identify early critical developmental windows for prevention and intervention.
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Affiliation(s)
| | - Amanda J. Law
- Corresponding Author: Amanda J. Law, PhD, Professor of Psychiatry, Medicine and Cell and Developmental Biology, Nancy L. Gary Endowed Chair in Children’s Mental Disorders Research, University of Colorado, School of Medicine, , Phone: 303-724-4418, Fax: 303-724-4425, 12700 E. 19th Ave., MS 8619, Aurora, CO 80045
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31
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James-Allan LB, Teal S, Powell TL, Jansson T. Changes in Placental Nutrient Transporter Protein Expression and Activity Across Gestation in Normal and Obese Women. Reprod Sci 2020; 27:1758-1769. [PMID: 32072607 DOI: 10.1007/s43032-020-00173-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 02/03/2020] [Indexed: 11/26/2022]
Abstract
Fetal growth and development are dependent on placental nutrient transport. The syncytiotrophoblast (ST) and its two polarized plasma membranes, the maternal-facing microvillous membrane (MVM) and fetal-facing basal membrane (BM), represent the primary barrier in the human placenta, controlling transplacental transfer of small solutes. MVM and BM nutrient transporter expression and activity are increased in obese mothers delivering large babies. However, placental nutrient transporter expression and activity in early gestation in normal and obese women are largely unknown. Placentas from normal BMI and obese women at 6-24 weeks of gestation, and term placentas from normal BMI women, were collected and ST plasma membranes isolated. The activity and protein expression of amino acid, glucose, and fatty acid transporters was assessed. No significant differences were observed in placental nutrient transporter protein expression between normal BMI and obese women in early pregnancy. In the MVM, system A amino acid activity (p = 0.02), SNAT2 (p < 0.0001), SNAT4 (p < 0.001), and GLUT1 (p = 0.01) protein expression were higher at term compared with early gestation. In contrast, MVM system L activity (p = 0.001), FATP4 (p = 0.03), and FATP6 (p = 0.009) protein expression were lower at term compared with early pregnancy. In the BM, there was no change in system L activity across gestation; however, BM FATP6 (p = 0.002) protein expression was lower at term compared with early pregnancy. These results suggest that placental transport of amino acids, glucose, and fatty acids are subjected to coordinated regulation across gestation to meet a fetal nutrient demand that changes with advancing pregnancy.
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Affiliation(s)
- Laura B James-Allan
- Department of Obstetrics/Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| | - Stephanie Teal
- Department of Obstetrics/Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Theresa L Powell
- Department of Obstetrics/Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Thomas Jansson
- Department of Obstetrics/Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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32
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Stremming J, Jansson T, Powell TL, Rozance PJ, Brown LD. Reduced Na + K + -ATPase activity may reduce amino acid uptake in intrauterine growth restricted fetal sheep muscle despite unchanged ex vivo amino acid transporter activity. J Physiol 2020; 598:1625-1639. [PMID: 31909825 DOI: 10.1113/jp278933] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 12/02/2019] [Indexed: 12/18/2022] Open
Abstract
KEY POINTS Fetuses with intrauterine growth restriction (IUGR) have reduced muscle mass that persists postnatally, which may contribute to their increased risk for adult onset metabolic diseases, such as diabetes and obesity. Amino acid transporter-mediated histidine uptake and system L amino acid transporter activity were similar in sarcolemmal membranes isolated from control and IUGR hindlimb skeletal muscle. Activity of Na+ K+ -ATPase, which is responsible for establishing the sodium gradient necessary for system A and N amino acid transporter function, was significantly reduced in IUGR skeletal muscle sarcolemma compared to control. ATP content was lower in IUGR skeletal muscle. Expression and phosphorylation of proteins in the mechanistic target of rapamycin pathway were similar in control and IUGR skeletal muscle homogenate. Our data suggest that lower Na+ K+ -ATPase activity, which reduces the driving force for active amino acid transport, and lower ATP availability contribute to reduced amino acid uptake and protein synthesis in IUGR fetal skeletal muscle. ABSTRACT Fetuses with intrauterine growth restriction (IUGR) have lower muscle mass that persists postnatally. Using a sheep model of placental insufficiency and IUGR, we have previously demonstrated lower net total uptake of amino acids by the fetal hindlimb and lower skeletal muscle protein synthesis rates. To investigate the mechanisms underlying these changes, we tested the hypothesis that ex vivo amino acid transporter and Na+ K+ -ATPase activity is reduced, and ex vivo ATP levels are lower in hindlimb skeletal muscle of the IUGR fetus. We developed a novel protocol to measure transporter-mediated histidine uptake, system L amino acid transporter activity and Na+ K+ -ATPase activity using sarcolemmal membranes isolated from hindlimb muscle of control (CON, n = 11-12) and IUGR (n = 12) late gestation fetal sheep. We also determined ATP content and the activity of insulin and mechanistic target of rapamycin (mTOR) signalling, which are involved in regulating cellular amino acid uptake and protein synthesis, by measuring the expression and phosphorylation of AKT, 4E-BP1, eIF2α, AMPKα, p70 S6 kinase and rpS6 in muscle homogenates. Transporter-mediated histidine uptake and system L activity were similar in control and IUGR sarcolemma, although ex vivo Na+ K+ -ATPase activity was lower by 64% (P = 0.019) in IUGR sarcolemma. ATP content was lower by 25% (P = 0.007) in IUGR muscle. Insulin, AMPK, and mTOR signalling activity was similar in control and IUGR muscle. We speculate that reduced muscle sarcolemmal Na+ K+ -ATPase activity and lower ATP content diminishes the sodium gradient in vivo, resulting in a reduced driving force for sodium-dependent transporters and subsequently lower muscle amino acid uptake.
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Affiliation(s)
- Jane Stremming
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Theresa L Powell
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Paul J Rozance
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Laura D Brown
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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Chassen S, Jansson T. Complex, coordinated and highly regulated changes in placental signaling and nutrient transport capacity in IUGR. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165373. [PMID: 30684642 PMCID: PMC6650384 DOI: 10.1016/j.bbadis.2018.12.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/20/2018] [Accepted: 12/26/2018] [Indexed: 01/01/2023]
Abstract
The most common cause of intrauterine growth restriction (IUGR) in the developed world is placental insufficiency, a concept often used synonymously with reduced utero-placental and umbilical blood flows. However, placental insufficiency and IUGR are associated with complex, coordinated and highly regulated changes in placental signaling and nutrient transport including inhibition of insulin and mTOR signaling and down-regulation of specific amino acid transporters, Na+/K+-ATPase, the Na+/H+-exchanger, folate and lactate transporters. In contrast, placental glucose transport capacity is unaltered and Ca2+-ATPase activity and the expression of proteins involved in placental lipid transport are increased in IUGR. These findings are not entirely consistent with the traditional view that the placenta is dysfunctional in IUGR, but rather suggest that the placenta adapts to reduce fetal growth in response to an inability of the mother to allocate resources to the fetus. This new model has implications for the understanding of the mechanisms underpinning IUGR and for the development of intervention strategies.
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Affiliation(s)
- Stephanie Chassen
- Department of Pediatrics, Division of Neonatology, University of Colorado, Anschutz Medical Campus, Aurora, USA
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, Division of Reproductive Sciences, University of Colorado, Anschutz Medical Campus, Aurora, USA.
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Vaughan OR, Thompson F, Lorca RA, Julian CG, Powell TL, Moore LG, Jansson T. Effect of high altitude on human placental amino acid transport. J Appl Physiol (1985) 2019; 128:127-133. [PMID: 31804891 DOI: 10.1152/japplphysiol.00691.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Women residing at high altitudes deliver infants of lower birth weight than at sea level. Birth weight correlates with placental system A-mediated amino acid transport capacity, and severe environmental hypoxia reduces system A activity in isolated trophoblast and the mouse placenta. However, the effect of high altitude on human placental amino acid transport remains unknown. We hypothesized that microvillous membrane (MVM) system A and system L amino acid transporter activity is lower in placentas of women living at high altitude compared with low-altitude controls. Placentas were collected at term from healthy pregnant women residing at high altitude (HA; >2,500 m; n = 14) or low altitude (LA; <1,700 m; n = 14) following planned, unlabored cesarean section. Birth weight, but not placenta weight, was 13% lower in HA pregnancies (2.88 ± 0.11 kg) compared with LA (3.30 ± 0.07 kg, P < 0.01). MVM erythropoietin receptor abundance, determined by immunoblot, was greater in HA than in LA placentas, consistent with lower placental oxygen levels at HA. However, there was no effect of altitude on MVM system A or L activity, determined by Na+-dependent [14C]methylaminoisobutyric acid uptake and [3H]leucine uptake, respectively. MVM abundance of glucose transporters (GLUTs) 1 and 4 and basal membrane GLUT4 were also similar in LA and HA placentas. Low birth weights in the neonates of women residing at high altitude are not a consequence of reduced placental amino acid transport capacity. These observations are in general agreement with studies of IUGR babies at low altitude, in which MVM system A activity is downregulated only in growth-restricted babies with significant compromise.NEW & NOTEWORTHY Babies born at high altitude are smaller than at sea level. Birth weight is dependent on growth in utero and, in turn, placental nutrient transport. We determined amino acid transport capacity in placentas collected from women resident at low and high altitude. Altitude did not affect system A amino acid transport across the syncytiotrophoblast microvillous membrane, suggesting that impaired placental amino acid transport does not contribute to reduced birth weight in this high-altitude population.
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Affiliation(s)
- Owen R Vaughan
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Fredrick Thompson
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Ramón A Lorca
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Colleen G Julian
- Department of Medicine University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Theresa L Powell
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado.,Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Lorna G Moore
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Thomas Jansson
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
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Obeticholic Acid Protects against Gestational Cholestasis-Induced Fetal Intrauterine Growth Restriction in Mice. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:7419249. [PMID: 31827696 PMCID: PMC6885290 DOI: 10.1155/2019/7419249] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/25/2019] [Accepted: 09/23/2019] [Indexed: 12/18/2022]
Abstract
Gestational cholestasis is a common disease and is associated with adverse pregnancy outcomes. However, there are still no effective treatments. We investigated the effects of obeticholic acid (OCA) on fetal intrauterine growth restriction (IUGR) during 17α-ethynylestradiol- (E2-) induced gestational cholestasis in mice. All pregnant mice except controls were subcutaneously injected with E2 (0.625 mg/kg) daily from gestational day (GD) 13 to GD17. Some pregnant mice were orally administered with OCA (5 mg/kg) daily from GD12 to GD17. As expected, OCA activated placental, maternal, and fetal hepatic FXR signaling. Additionally, exposure with E2 during late pregnancy induced cholestasis, whereas OCA alleviated E2-induced cholestasis. Gestational cholestasis caused reduction of fetal weight and crown-rump length and elevated the incidence of IUGR. OCA decreased the incidence of IUGR during cholestasis. Interestingly, OCA attenuated reduction of blood sinusoid area in placental labyrinth layer and inhibited downregulation of placental sodium-coupled neutral amino acid transporter- (SNAT-) 2 during cholestasis. Additional experiment found that OCA attenuated glutathione depletion and lipid peroxidation in placenta and fetal liver and placental protein nitration during cholestasis. Moreover, OCA inhibited the upregulation of placental NADPH oxidase-4 and antioxidant genes during cholestasis. OCA activated antioxidant Nrf2 signaling during cholestasis. Overall, we demonstrated that OCA treatment protected against gestational cholestasis-induced placental dysfunction and IUGR through suppressing placental oxidative stress and maintaining bile acid homeostasis.
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Menchini RJ, Chaudhry FA. Multifaceted regulation of the system A transporter Slc38a2 suggests nanoscale regulation of amino acid metabolism and cellular signaling. Neuropharmacology 2019; 161:107789. [PMID: 31574264 DOI: 10.1016/j.neuropharm.2019.107789] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 09/16/2019] [Accepted: 09/20/2019] [Indexed: 02/07/2023]
Abstract
Amino acids are essential for cellular protein synthesis, growth, metabolism, signaling and in stress responses. Cell plasma membranes harbor specialized transporters accumulating amino acids to support a variety of cellular biochemical pathways. Several transporters for neutral amino acids have been characterized. However, Slc38a2 (also known as SA1, SAT2, ATA2, SNAT2) representing the classical transport system A activity stands in a unique position: Being a secondarily active transporter energized by the electrochemical gradient of Na+, it creates steep concentration gradients for amino acids such as glutamine: this may subsequently drive the accumulation of additional neutral amino acids through exchange via transport systems ASC and L. Slc38a2 is ubiquitously expressed, yet in a cell-specific manner. In this review, we show that Slc38a2 is regulated at the transcriptional and translational levels as well as by ions and proteins through direct interactions. We describe how Slc38a2 senses amino acid availability and passes this onto intracellular signaling pathways and how it regulates protein synthesis, cellular proliferation and apoptosis through the mechanistic (mammalian) target of rapamycin (mTOR) and general control nonderepressible 2 (GCN2) pathways. Furthermore, we review how this extensively regulated transporter contributes to cellular osmoadaptation and how it is regulated by endoplasmic reticulum stress and various hormonal stimuli to promote cellular metabolism, cellular signaling and cell survival. This article is part of the issue entitled 'Special Issue on Neurotransmitter Transporters'.
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Affiliation(s)
| | - Farrukh Abbas Chaudhry
- Department of Molecular Medicine, University of Oslo, Oslo, Norway; Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway
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Rousseau-Ralliard D, Valentino SA, Aubrière MC, Dahirel M, Lallemand MS, Archilla C, Jouneau L, Fournier N, Richard C, Aioun J, Vitorino Carvalho A, Jérôme L, Slama R, Duranthon V, Cassee FR, Chavatte-Palmer P, Couturier-Tarrade A. Effects of first-generation in utero exposure to diesel engine exhaust on second-generation placental function, fatty acid profiles and foetal metabolism in rabbits: preliminary results. Sci Rep 2019; 9:9710. [PMID: 31273257 PMCID: PMC6609606 DOI: 10.1038/s41598-019-46130-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 06/19/2019] [Indexed: 12/19/2022] Open
Abstract
Atmospheric pollution has major health effects on directly exposed subjects but intergenerational consequences are poorly characterized. We previously reported that diesel engine exhaust (DE) could lead to structural changes in the placenta of in utero exposed rabbits (first generation, F1). The effects of maternal exposure to DE were further studied on second-generation (F2) rabbits. Pregnant F0 females were exposed to filtered, diluted DE (1 mg/m3, median particle diameter: 69 nm) or clean filtered air (controls) for 2 h/day, 5 days/week by nose-only exposure during days 3–27 post-conception (dpc). Adult female offspring (F1) were mated to control males: F1 tissues and F2 foeto-placental units were collected at 28 dpc and placental structure and gene expression (microarray) analysed. Fatty acid profiles were determined in foetal and maternal plasma, maternal liver and placenta. In F1, compared to controls, hepatic neutral lipid contents were increased in exposed animals without change in the blood biochemistry. In F2, the placental lipid contents were higher, with higher monounsaturated fatty acids and reduced pro-inflammatory arachidonic acid (AA), without placental structural changes. Conversely, the proportion of anti-inflammatory n-3 polyunsaturated fatty acids in F2 plasma was increased while that of AA was decreased. Gene set enrichment analyses (GSEA) of F2 placenta transcriptomic data identified that the proteasome complex and ubiquitin pathways genes were over-represented and ion channel function and inflammation pathways genes were under-represented in exposed animals. These preliminary results demonstrate that diesel engine exhaust exposure and in utero indirect exposure should be considered as a programming factor within the context of the DOHaD (Developmental Origins of Health and Disease) with a probable intergenerational transmission.
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Affiliation(s)
- Delphine Rousseau-Ralliard
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France. .,PremUp Foundation, Paris, France.
| | - Sarah A Valentino
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France.,PremUp Foundation, Paris, France
| | - Marie-Christine Aubrière
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France.,PremUp Foundation, Paris, France
| | - Michèle Dahirel
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France.,PremUp Foundation, Paris, France
| | - Marie-Sylvie Lallemand
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France.,PremUp Foundation, Paris, France
| | | | - Luc Jouneau
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France
| | - Natalie Fournier
- University Paris-Sud, EA 4041/4529 Lip (Sys)2, UFR de Pharmacie, Châtenay-Malabry, France.,Hôpital Européen Georges Pompidou (AP-HP), Laboratoire de Biochimie, UF Cardio-Vasculaire, Paris, France
| | - Christophe Richard
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France.,PremUp Foundation, Paris, France
| | - Josiane Aioun
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France.,PremUp Foundation, Paris, France
| | | | | | - Rémy Slama
- Inserm, Univ. Grenoble Alpes, CNRS, IAB joint Research Center, Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health, Grenoble, France
| | | | - Flemming R Cassee
- Centre for Sustainability, Environment and Health, National Institute for Public Health and the Environment, Bilthoven, Netherlands.,Institute of Risk Assessment Sciences, Utrecht University, Utrecht, Netherlands
| | - Pascale Chavatte-Palmer
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France.,PremUp Foundation, Paris, France
| | - Anne Couturier-Tarrade
- UMR BDR, INRA, ENVA, Université Paris Saclay, Jouy en Josas, France. .,PremUp Foundation, Paris, France.
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Luo Z, Xu X, Sho T, Luo W, Zhang J, Xu W, Yao J, Xu J. Effects of n-acetyl-cysteine supplementation in late gestational diet on maternal-placental redox status, placental NLRP3 inflammasome, and fecal microbiota in sows1. J Anim Sci 2019; 97:1757-1771. [PMID: 30789643 DOI: 10.1093/jas/skz058] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 02/05/2019] [Indexed: 12/14/2022] Open
Abstract
Although n-acetyl-cysteine (NAC) has been shown to efficiently alleviate oxidative stress, inflammatory response, and alter gut microbiota, little attention has been focused on their interactions with placental metabolic status of sows. The effects of NAC on the placental redox status, function, inflammasome, and fecal microbiota in sows were explored to clarify the correlation between the fecal microbiota and placenta. Sows were divided into either the control group or the NAC group which received dietary 0.5% NAC supplementation from day 85 of gestation to delivery. Plasma redox status, placental growth factors, nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome, fecal microbial metabolites, and communities were evaluated. Compared with the control group, although NAC did not ameliorate reproductive performance of sows (P > 0.05), it significantly improved maternal-placental health, which was accompanied by increased activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), decreased level of malondialdehyde (MDA), and lowered expression of interleukin (IL)-1β and IL-18 through inhibiting NLRP3 inflammasome (P < 0.05). Additionally, NAC significantly increased placental insulin-like growth factors (IGFs) and E-cadherin contents (P < 0.05), elevated the expression of genes involved in angiogenesis and amino acids transporters (P < 0.05), and decreased the microtubule-associated protein light chain 3B (LC3B) and Beclin-1 protein expression (P < 0.05). Furthermore, NAC increased the relative abundances of fecal Prevotella, Clostridium cluster XIVa, and Roseburial/Eubacterium rectale (P < 0.05), which were negatively correlated with placental NLRP3 and positively with solute carrier family 7, member 8 (Slc7a8; P < 0.05). In conclusion, NAC supplementation during late gestation alleviated maternal-placental oxidative stress and inflammatory response, improved placental function, and altered fecal microbial communities.
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Affiliation(s)
- Zhen Luo
- School of Agriculture and Biology, Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xue Xu
- School of Agriculture and Biology, Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Takami Sho
- School of Agriculture and Biology, Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Wenli Luo
- School of Agriculture and Biology, Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Jing Zhang
- School of Agriculture and Biology, Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Weina Xu
- School of Agriculture and Biology, Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Jianbo Yao
- Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV
| | - Jianxiong Xu
- School of Agriculture and Biology, Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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TRAF4 positively regulates the osteogenic differentiation of mesenchymal stem cells by acting as an E3 ubiquitin ligase to degrade Smurf2. Cell Death Differ 2019; 26:2652-2666. [PMID: 31076633 PMCID: PMC7224386 DOI: 10.1038/s41418-019-0328-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 03/13/2019] [Accepted: 03/22/2019] [Indexed: 01/25/2023] Open
Abstract
TNF receptor-associated factor 4 (TRAF4), a member of the TRAF family, plays an important role in the embryogenesis and development of the bone system. Mesenchymal stem cells (MSCs), which are the primary origin of osteoblasts in vivo, are key cells in bone development; however, whether TRAF4 modulates the osteogenic capacity of MSCs has never been explored. In this study, we demonstrated that TRAF4 positively regulates the osteogenic process of MSCs both in vitro and in vivo. In addition, we further demonstrated that TRAF4 modulates the osteogenic process of MSCs by acting as an E3 ubiquitin ligase to mediate the K48-linked ubiquitination of Smurf2 at the K119 site and cause degradation. Furthermore, TRAF4 was abnormally decreased in bone sections of ovariectomized rat and osteoporosis patients. Taken together, our findings suggest that TRAF4 positively regulates the osteogenic differentiation of MSCs by acting as an E3 ubiquitin ligase to degrade Smurf2. These results emphasize the critical role of TRAF4 in bone formation and could not only improve the clinical use of MSCs in tissue engineering but also clarify the pathogenesis of bone metabolism disorders.
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Abstract
Apelin is an insulin-sensitizing hormone increased in abundance with obesity. Apelin and its receptor, APJ, are expressed in the human placenta, but whether apelin regulates placental function in normal body mass index (BMI) and obese pregnant women remains unknown. We hypothesized that apelin stimulates amino acid transport in cultured primary human trophoblast (PHT) cells and that maternal circulating apelin levels are elevated in obese pregnant women delivering large babies. Treating PHT cells with physiological concentrations of the pyroglutamated form [Pyr1]apelin-13 (0.1-10.0 ng/ml) for 24 h dose-dependently increased System A amino acid transport (P < 0.05) but did not affect System L transport activity. Mechanistic target of rapamycin (mTOR), extracellular signal-regulated kinase-1/2 (ERK1/2), and AMP-activated protein kinase-α (AMPKα) signaling were unaffected by apelin (P > 0.05). Plasma apelin was not different in obese women (BMI 35.8 ± 0.7, n = 21) with large babies compared with normal-BMI women (23.1 ± 0.5, n = 16) delivering normal birth weight infants. Apelin was highly expressed in placental villous tissue (20-fold higher vs. adipose), and APJ was present in syncytiotrophoblast microvillous membrane, but neither differed in abundance between normal-BMI and obese women. Phosphorylation (Thr172) of placental AMPKα strongly correlated with microvillous membrane APJ expression (P < 0.01, R = 0.63) but negatively correlated with placental apelin abundance (P < 0.01, R = -0.62). Neither placental APJ nor apelin abundance correlated with maternal BMI, plasma insulin, birth weight, or mTOR or ERK1/2 signaling (P > 0.05). Hence, apelin stimulates trophoblast amino acid uptake, establishing a novel mechanism regulating placental function. We found no evidence that apelin constitutes an endocrine link between maternal obesity and fetal overgrowth.
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Affiliation(s)
- O R Vaughan
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - T L Powell
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus , Aurora, Colorado
- Department of Pediatrics, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - T Jansson
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus , Aurora, Colorado
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Roberti SL, Higa R, White V, Powell TL, Jansson T, Jawerbaum A. Critical role of mTOR, PPARγ and PPARδ signaling in regulating early pregnancy decidual function, embryo viability and feto-placental growth. Mol Hum Reprod 2019. [PMID: 29538677 DOI: 10.1093/molehr/gay013] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
STUDY QUESTION What are the consequences of inhibiting mTOR, the mechanistic target of rapamycin (mTOR), and the peroxisome proliferator activated receptor gamma (PPARγ) and PPARδ pathways in the early post-implantation period on decidual function, embryo viability and feto-placental growth in the rat? SUMMARY ANSWER mTOR inhibition from Days 7 to 9 of pregnancy in rats caused decidual PPARγ and PPARδ upregulation on Day 9 of pregnancy and resulted in embryo resorption by Day 14 of pregnancy. PPARγ and PPARδ inhibition differentially affected decidual mTOR signaling and levels of target proteins relevant to lipid histotrophic nutrition and led to reduced feto-placental weights on Day 14 of pregnancy. WHAT IS KNOWN ALREADY Although mTOR, PPARγ and PPARδ are nutrient sensors important during implantation, the role of these signaling pathways in decidual function and how they interact in the early post-implantation period are unknown. Perilipin 2 (PLIN2) and fatty acid binding protein 4 (FABP4), two adipogenic proteins involved in lipid histotrophic nutrition, are targets of mTOR and PPAR signaling pathways in a variety of tissues. STUDY DESIGN, SIZE, DURATION Rapamycin (mTOR inhibitor, 0.75 mg/kg, sc), T0070907 (PPARγ inhibitor, 0.001 mg/kg, sc), GSK0660 (PPARδ inhibitor, 0.1 mg/kg, sc) or vehicle was injected daily to pregnant rats from Days 7 to 9 of pregnancy and the studies were performed on Day 9 of pregnancy (n = 7 per group) or Day 14 of pregnancy (n = 7 per group). PARTICIPANTS/MATERIALS, SETTING, METHODS On Day 9 of pregnancy, rat decidua were collected and prepared for western blot and immunohistochemical studies. On Day 14 of pregnancy, the resorption rate, number of viable fetuses, crown-rump length and placental and decidual weights were determined. MAIN RESULTS AND THE ROLE OF CHANCE Inhibition of mTOR in the early post-implantation period led to a reduction in FABP4 protein levels, an increase in PLIN2 levels and an upregulation of PPARγ and PPARδ in 9-day-pregnant rat decidua. Most embryos were viable on Day 9 of pregnancy but had resorbed by Day 14 of pregnancy. This denotes a key function of mTOR in the post-implantation period and suggests that activation of PPAR signaling was insufficient to compensate for impaired nutritional/survival signaling induced by mTOR inhibition. Inhibition of PPARγ signaling resulted in decreased decidual PLIN2 and FABP4 protein expression as well as in inhibition of decidual mTOR signaling in Day 9 of pregnancy. This treatment also reduced feto-placental growth on Day 14 of pregnancy, revealing the relevance of PPARγ signaling in sustaining post-implantation growth. Moreover, following inhibition of PPARδ, PLIN2 levels were decreased and mTOR complex 1 and 2 signaling was altered in decidua on Day 9 of pregnancy. On Day 14 of pregnancy, PPARδ inhibition caused reduced feto-placental weight, increased decidual weight and increased resorption rate, suggesting a key role of PPARδ in sustaining post-implantation development. LARGE SCALE DATA Not applicable. LIMITATIONS, REASONS FOR CAUTION This is an in vivo animal study and the relevance of the results for humans remains to be established. WIDER IMPLICATIONS OF THE FINDINGS The early post-implantation period is a critical window of development and changes in the intrauterine environment may cause embryo resorption and lead to placental and fetal growth restriction. mTOR, PPARγ and PPARδ signaling are decidual nutrient sensors with extensive cross-talk that regulates adipogenic proteins involved in histotrophic nutrition and important for embryo viability and early placental and fetal development and growth. STUDY FUNDING/COMPETING INTEREST(S) Funding was provided by the Agencia Nacional de Promoción Científica y Tecnológica de Argentina (PICT 2014-411 and PICT 2015-0130), and by the International Cooperation (Grants CONICET-NIH-2014 and CONICET-NIH-2017) to A.J. and T.J. The authors have no conflicts of interest.
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Affiliation(s)
- Sabrina L Roberti
- Universidad de Buenos Aires, Facultad de Medicina, Paraguay 2155, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Laboratory of Reproduction and Metabolism, CEFYBO, 1121 CABA, Buenos Aires, Argentina
| | - Romina Higa
- Universidad de Buenos Aires, Facultad de Medicina, Paraguay 2155, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Laboratory of Reproduction and Metabolism, CEFYBO, 1121 CABA, Buenos Aires, Argentina
| | - Verónica White
- Universidad de Buenos Aires, Facultad de Medicina, Paraguay 2155, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Laboratory of Reproduction and Metabolism, CEFYBO, 1121 CABA, Buenos Aires, Argentina
| | - Theresa L Powell
- Section of Neonatology, Department of Pediatrics, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA.,Division of Reproductive Sciences, Department of OB/GYN, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of OB/GYN, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Alicia Jawerbaum
- Universidad de Buenos Aires, Facultad de Medicina, Paraguay 2155, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Laboratory of Reproduction and Metabolism, CEFYBO, 1121 CABA, Buenos Aires, Argentina
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Gupta MB, Jansson T. Novel roles of mechanistic target of rapamycin signaling in regulating fetal growth†. Biol Reprod 2019; 100:872-884. [PMID: 30476008 PMCID: PMC6698747 DOI: 10.1093/biolre/ioy249] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/08/2018] [Accepted: 11/19/2018] [Indexed: 12/18/2022] Open
Abstract
Mechanistic target of rapamycin (mTOR) signaling functions as a central regulator of cellular metabolism, growth, and survival in response to hormones, growth factors, nutrients, energy, and stress signals. Mechanistic TOR is therefore critical for the growth of most fetal organs, and global mTOR deletion is embryonic lethal. This review discusses emerging evidence suggesting that mTOR signaling also has a role as a critical hub in the overall homeostatic control of fetal growth, adjusting the fetal growth trajectory according to the ability of the maternal supply line to support fetal growth. In the fetus, liver mTOR governs the secretion and phosphorylation of insulin-like growth factor binding protein 1 (IGFBP-1) thereby controlling the bioavailability of insulin-like growth factors (IGF-I and IGF-II), which function as important growth hormones during fetal life. In the placenta, mTOR responds to a large number of growth-related signals, including amino acids, glucose, oxygen, folate, and growth factors, to regulate trophoblast mitochondrial respiration, nutrient transport, and protein synthesis, thereby influencing fetal growth. In the maternal compartment, mTOR is an integral part of a decidual nutrient sensor which links oxygen and nutrient availability to the phosphorylation of IGFBP-1 with preferential effects on the bioavailability of IGF-I in the maternal-fetal interface and in the maternal circulation. These new roles of mTOR signaling in the regulation fetal growth will help us better understand the molecular underpinnings of abnormal fetal growth, such as intrauterine growth restriction and fetal overgrowth, and may represent novel avenues for diagnostics and intervention in important pregnancy complications.
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Affiliation(s)
- Madhulika B Gupta
- Department of Pediatrics, University of Western Ontario, London, Ontario, Canada
- Department of Biochemistry, University of Western Ontario, London, Ontario, Canada
- Children's Health Research Institute, London, Ontario, Canada
| | - Thomas Jansson
- Department of Obstetrics and Gynecology, Division of Reproductive Sciences, University of Colorado | Anschutz Medical Campus, Aurora, Colorado, USA
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Ma YF, Batistel F, Xu TL, Han LQ, Bucktrout R, Liang Y, Coleman DN, Parys C, Loor JJ. Phosphorylation of AKT serine/threonine kinase and abundance of milk protein synthesis gene networks in mammary tissue in response to supply of methionine in periparturient Holstein cows. J Dairy Sci 2019; 102:4264-4274. [PMID: 30879806 DOI: 10.3168/jds.2018-15451] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 01/25/2019] [Indexed: 12/17/2022]
Abstract
The main objective was to evaluate the effect of increasing the supply of Met around parturition on abundance and phosphorylation of insulin- and mechanistic target of rapamycin complex 1 (mTORC1)-related signaling proteins along with mRNA abundance of milk protein and fat synthesis-related genes in postpartal mammary tissue. A basal control diet (control) or the basal diet plus ethyl-cellulose rumen-protected Met (0.9 g/kg of dry matter intake; Mepron, Evonik Nutrition & Care GmbH, Hanau-Wolfgang, Germany) were fed (n = 30 cows/diet) from d -28 to 60 relative to parturition. Mammary tissue and blood plasma were harvested from the same cows (n = 5/diet) in the control and Met groups at d 21 postpartum for mRNA, protein, and AA analysis. Increasing the supply of Met led to greater milk protein percentage and milk yield along with greater ratio of phosphorylated (p-)AKT to total AKT. The ratio of p-mTORC1 to total mTORC1 did not differ, but ratio of p-RPS6 to total ribosomal protein S6 (RPS6) was lower in response to Met supply. These responses were associated with greater mRNA abundance of the signaling proteins Janus kinase 2 (JAK2) and insulin receptor substrate 1 (IRS1). Greater Met supply also upregulated mRNA abundance of high-affinity cationic (SLC7A1) and sodium-coupled AA transporters (SLC38A1, SLC38A2); leucyl-tRNA (LARS), valyl-tRNA (VARS), and isoleucyl-tRNA synthetases (IARS); glucose transport solute carrier family 2 member 3 (SLC2A1); glucose transport solute carrier family 2 member 3 (SLC2A3); and casein α-s1 (CSN1S1). The mRNA abundance of components of the unfolded protein response, such as x-box binding protein 1 (XBP1) and activating transcription factor 6 (ATF6), were upregulated, and protein phosphatase 1, regulatory subunit 15A (PPP1R15A) was downregulated in response to greater Met supply. Overall, the data suggest that increased dry matter intake, greater phosphorylation status of AKT, upregulation of glucose and AA transporters, and transcripts of tRNases in response to enhanced Met supply might have compensated for a reduction in ribosome biogenesis due to a lower ratio of p-RPS6 to total RPS6. Together, these cellular responses constitute a mechanism whereby Met supply can regulate milk protein synthesis in early lactation.
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Affiliation(s)
- Y F Ma
- Institute of Animal Nutrition and Feed, Inner Mongolia Academy of Agriculture and Animal Husbandry Sciences, Hohhot 010031, P. R. China; Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - F Batistel
- Department of Animal, Dairy & Veterinary Science, Utah State University, Logan 84322
| | - T L Xu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - L Q Han
- Department of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, P. R. China
| | - R Bucktrout
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - Y Liang
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - D N Coleman
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - C Parys
- Evonik Nutrition & Care GmbH, Hanau-Wolfgang, 63457, Germany
| | - J J Loor
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801.
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44
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Stojanovska V, Dijkstra DJ, Vogtmann R, Gellhaus A, Scherjon SA, Plösch T. A double-hit pre-eclampsia model results in sex-specific growth restriction patterns. Dis Model Mech 2019; 12:dmm.035980. [PMID: 30683649 PMCID: PMC6398487 DOI: 10.1242/dmm.035980] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 01/09/2019] [Indexed: 12/29/2022] Open
Abstract
Pre-eclampsia is a multifactorial pregnancy-associated disorder characterized by angiogenic dysbalance and systemic inflammation; however, animal models that combine these two pathophysiological conditions are missing. Here, we introduce a novel double-hit pre-eclampsia mouse model that mimics the complex multifactorial conditions present during pre-eclampsia and allows for the investigation of early consequences for the fetus. Adenoviral overexpression of soluble fms-like tyrosine kinase (sFlt-1) and lipopolysaccharide (LPS) administration at mid-gestation in pregnant mice resulted in hypertension and albuminuria comparable to that of the manifestation in humans. A metabolomics analysis revealed that pre-eclamptic dams have increased plasma concentrations of phosphadytilcholines. The fetuses of both sexes were growth restricted; however, in males a brain-sparing effect was seen as compensation for this growth restriction. According to the plasma metabolomics, male fetuses showed changes in amino acid metabolism, while female fetuses showed pronounced alterations in lipid metabolism. Our results show that combined exposure to sFlt-1 and LPS mimics the clinical symptoms of pre-eclampsia and affects fetal growth in a sex-specific manner, with accompanying metabolome changes.
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Affiliation(s)
- Violeta Stojanovska
- Department of Obstetrics and Gynecology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Dorieke J Dijkstra
- Department of Obstetrics and Gynecology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Rebekka Vogtmann
- Department of Gynecology and Obstetrics, University Hospital Duisburg-Essen, 45147 Essen, Germany
| | - Alexandra Gellhaus
- Department of Gynecology and Obstetrics, University Hospital Duisburg-Essen, 45147 Essen, Germany
| | - Sicco A Scherjon
- Department of Obstetrics and Gynecology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
| | - Torsten Plösch
- Department of Obstetrics and Gynecology, University Medical Center Groningen, University of Groningen, 9700RB Groningen, The Netherlands
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Rosario FJ, Gupta MB, Myatt L, Powell TL, Glenn JP, Cox L, Jansson T. Mechanistic Target of Rapamycin Complex 1 Promotes the Expression of Genes Encoding Electron Transport Chain Proteins and Stimulates Oxidative Phosphorylation in Primary Human Trophoblast Cells by Regulating Mitochondrial Biogenesis. Sci Rep 2019; 9:246. [PMID: 30670706 PMCID: PMC6343003 DOI: 10.1038/s41598-018-36265-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 11/13/2018] [Indexed: 01/06/2023] Open
Abstract
Trophoblast oxidative phosphorylation provides energy for active transport and protein synthesis, which are critical placental functions influencing fetal growth and long-term health. The molecular mechanisms regulating trophoblast mitochondrial oxidative phosphorylation are largely unknown. We hypothesized that mechanistic Target of Rapamycin Complex 1 (mTORC1) is a positive regulator of key genes encoding Electron Transport Chain (ETC) proteins and stimulates oxidative phosphorylation in trophoblast and that ETC protein expression is down-regulated in placentas of infants with intrauterine growth restriction (IUGR). We silenced raptor (mTORC1 inhibition), rictor (mTORC2 inhibition) or DEPTOR (mTORC1/2 activation) in cultured term primary human trophoblast (PHT) cells. mTORC1 inhibition caused a coordinated down-regulation of 18 genes encoding ETC proteins representing all ETC complexes. Inhibition of mTORC1, but not mTORC2, decreased protein expression of ETC complexes I–IV, mitochondrial basal, ATP coupled and maximal respiration, reserve capacity and proton leak, whereas activation of mTORC1 had the opposite effects. Moreover, placental protein expression of ETC complexes was decreased and positively correlated to mTOR signaling activity in IUGR. By controlling trophoblast ATP production, mTORC1 links nutrient and O2 availability and growth factor signaling to placental function and fetal growth. Reduced placental mTOR activity may impair mitochondrial respiration and contribute to placental insufficiency in IUGR pregnancies.
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Affiliation(s)
- Fredrick J Rosario
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| | - Madhulika B Gupta
- Children's Health Research Institute and Department of Pediatrics and Biochemistry, University of Western Ontario, London, Ontario, N6A 5C1, Canada
| | - Leslie Myatt
- Department of Obstetrics and Gynecology, Oregon Health and Science University, Portland, USA
| | - Theresa L Powell
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Section of Neonatology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Jeremy P Glenn
- Department of Genetics, Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Laura Cox
- Department of Genetics, Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA.,Department of Internal Medicine, Section of Molecular Medicine and Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Thomas Jansson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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46
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Cleal JK, Lofthouse EM, Sengers BG, Lewis RM. A systems perspective on placental amino acid transport. J Physiol 2018; 596:5511-5522. [PMID: 29984402 PMCID: PMC6265537 DOI: 10.1113/jp274883] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 05/29/2018] [Indexed: 12/22/2022] Open
Abstract
Placental amino acid transfer is a complex process that is essential for fetal development. Impaired amino acid transfer causes fetal growth restriction, which may have lifelong health consequences. Transepithelial transfer of amino acids across the placental syncytiotrophoblast requires accumulative, exchange and facilitated transporters on the apical and basal membranes to work in concert. However, transporters alone do not determine amino acid transfer and factors that affect substrate availability, such as blood flow and metabolism, may also become rate-limiting for transfer. In order to determine the rate-limiting processes, it is necessary to take a systems approach which recognises the interdependence of these processes. New technologies have the potential to deliver targeted interventions to the placenta and help poorly growing fetuses. While many factors are necessary for amino acid transfer, novel therapies need to target the rate-limiting factors if they are going to be effective. This review will outline the factors which determine amino acid transfer and describe how they become interdependent. It will also highlight the role of computational modelling as a tool to understand this process.
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Affiliation(s)
- Jane K. Cleal
- Faculty of MedicineUniversity of SouthamptonSouthamptonUK
- Institute of Life SciencesUniversity of SouthamptonSouthamptonUK
| | - Emma M. Lofthouse
- Faculty of MedicineUniversity of SouthamptonSouthamptonUK
- Institute of Life SciencesUniversity of SouthamptonSouthamptonUK
| | - Bram G. Sengers
- Institute of Life SciencesUniversity of SouthamptonSouthamptonUK
- Faculty of Engineering and the EnvironmentUniversity of SouthamptonSouthamptonUK
| | - Rohan M. Lewis
- Faculty of MedicineUniversity of SouthamptonSouthamptonUK
- Institute of Life SciencesUniversity of SouthamptonSouthamptonUK
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47
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Chen YY, Gupta MB, Grattton R, Powell TL, Jansson T. Down-regulation of placental folate transporters in intrauterine growth restriction. J Nutr Biochem 2018; 59:136-141. [PMID: 29986308 PMCID: PMC6129407 DOI: 10.1016/j.jnutbio.2018.06.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/13/2018] [Accepted: 06/06/2018] [Indexed: 11/21/2022]
Abstract
Folate deficiency in pregnancy is associated with neural tube defects, restricted fetal growth and fetal programming of diseases later in life. Fetal folate availability is dependent on maternal folate levels and placental folate transport capacity, mediated by two key transporters, Folate Receptor-α and Reduced Folate Carrier (RFC). We tested the hypothesis that intrauterine growth restriction (IUGR) is associated with decreased folate transporter expression and activity in isolated syncytiotrophoblast microvillous plasma membranes (MVM). Women with pregnancies complicated by IUGR (birth weight <3rd percentile, mean birth weight 1804±110 g, gestational age 35.7±0.61 weeks, n=25) and women delivering an appropriately-for gestational age infant (control group, birth weight 25th-75th centile, mean birth weight 2493±216 g, gestational age 33.9±0.95 weeks, n=19) were recruited and placentas were collected at delivery. MVM was isolated and folate transporter protein expression was measured using Western blot and transporter activity was determined using radiolabelled methyltetrahydrofolic acid and rapid filtration. Whereas the expression of FR-α was unaffected, MVM RFC protein expression was significantly decreased in the IUGR group (-34%, P<.05). IUGR MVM had a significantly lower folate uptake compared to the control group (-38%, P<.05). In conclusion, placental folate transport capacity is decreased in IUGR, which may contribute to the restricted fetal growth and intrauterine programming of childhood and adult disease. These findings suggest that continuation of folate supplementation in the second and third trimester is of particular importance in pregnancies complicated by IUGR.
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Affiliation(s)
- Yi-Yung Chen
- Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus Aurora, CO, USA; Division of High-risk Pregnancy, Department of Obstetrics & Gynecology, Mackay Memorial Hospital, Taipei, Taiwan.
| | - Madhulika B Gupta
- Children's Health Research Institute, University of Western Ontario, London, ON, Canada; Department of Pediatrics and Biochemistry, University of Western Ontario, London, ON, Canada.
| | - Rob Grattton
- Department of Obstetrics and Gynecology, University of Western Ontario, London, ON, Canada.
| | - Theresa L Powell
- Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus Aurora, CO, USA; Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| | - Thomas Jansson
- Department of Obstetrics & Gynecology, University of Colorado Anschutz Medical Campus Aurora, CO, USA.
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48
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Jeckel KM, Boyarko AC, Bouma GJ, Winger QA, Anthony RV. Chorionic somatomammotropin impacts early fetal growth and placental gene expression. J Endocrinol 2018; 237:301-310. [PMID: 29661800 PMCID: PMC5953842 DOI: 10.1530/joe-18-0093] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 04/16/2018] [Indexed: 12/16/2022]
Abstract
Several developmental windows, including placentation, must be negotiated to establish and maintain pregnancy. Impaired placental function can lead to preeclampsia and/or intrauterine growth restriction (IUGR), resulting in increased infant mortality and morbidity. It has been hypothesized that chorionic somatomammotropin (CSH) plays a significant role in fetal development, potentially by modifying maternal and fetal metabolism. Recently, using lentiviral-mediated in vivo RNA interference in sheep, we demonstrated significant reductions in near-term (135 days of gestation; dGA) fetal and placental size, and altered fetal liver gene expression, resulting from CSH deficiency. We sought to examine the impact of CSH deficiency on fetal and placental size earlier in gestation (50 dGA), and to examine placental gene expression at 50 and 135 dGA. At 50 dGA, CSH-deficient pregnancies exhibited a 41% reduction (P ≤ 0.05) in uterine vein concentrations of CSH, and significant (P ≤ 0.05) reductions (≈21%) in both fetal body and liver weights. Placentae harvested at 50 and 135 dGA exhibited reductions in IGF1 and IGF2 mRNA concentrations, along with reductions in SLC2A1 and SLC2A3 mRNA. By contrast, mRNA concentrations for various members of the System A, System L and System y+ amino acid transporter families were not significantly impacted. The IUGR observed at the end of the first-third of gestation indicates that the near-term IUGR reported previously, began early in gestation, and may have in part resulted from deficits in the paracrine action of CSH within the placenta. These results provide further compelling evidence for the importance of CSH in the progression and outcome of pregnancy.
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Affiliation(s)
- K M Jeckel
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - A C Boyarko
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - G J Bouma
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Q A Winger
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - R V Anthony
- Animal Reproduction and Biotechnology LaboratoryDepartment of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
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Ge Y, Gu Y, Wang J, Zhang Z. Membrane topology of rat sodium-coupled neutral amino acid transporter 2 (SNAT2). BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1460-1469. [PMID: 29678469 DOI: 10.1016/j.bbamem.2018.04.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 03/24/2018] [Accepted: 04/15/2018] [Indexed: 11/19/2022]
Abstract
Sodium-coupled neutral amino acid transporter 2 (SNAT2) is a subtype of the amino acid transport system A that is widely expressed in mammalian tissues. It plays critical roles in glutamic acid-glutamine circulation, liver gluconeogenesis and other biological pathway. However, the topology of the SNAT2 amino acid transporter is unknown. Here we identified the topological structure of SNAT2 using bioinformatics analysis, Methoxy-polyethylene glycol maleimide (mPEG-Mal) chemical modification, protease cleavage assays, immunofluorescence and examination of glycosylation. Our results show that SNAT2 contains 11 transmembrane domains (TMDs) with an intracellular N terminus and an extracellular C terminus. Three N-glycosylation sites were verified at the largest extracellular loop. This model is consistent with the previous model of SNAT2 with the exception of a difference in number of glycosylation sites. This is the first time to confirm the SNAT2 membrane topology using experimental methods. Our study on SNAT2 topology provides valuable structural information of one of the solute carrier family 38 (SLC38) members.
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Affiliation(s)
- Yudan Ge
- College of Life Sciences and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang City 110016, China
| | - Yanting Gu
- College of Life Sciences and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang City 110016, China
| | - Jiahong Wang
- College of Life Sciences and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang City 110016, China
| | - Zhou Zhang
- College of Life Sciences and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang City 110016, China.
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50
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Alterations in placental long chain polyunsaturated fatty acid metabolism in human intrauterine growth restriction. Clin Sci (Lond) 2018; 132:595-607. [PMID: 29463583 DOI: 10.1042/cs20171340] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 02/19/2018] [Accepted: 02/20/2018] [Indexed: 12/15/2022]
Abstract
Fatty acids (FA) are critical for fetal brain development and are transferred across the placenta by membrane-bound FA transport proteins (FATP), translocases (FAT/CD36), and cytosolic binding proteins (FABP). The cytosolic protein perilipin-2 aids in neutral lipid storage within lipid droplets. Decreased placental nutrient transport is believed to contribute to intrauterine growth restriction (IUGR); however, IUGR placental lipid transport and metabolism are poorly understood. We hypothesized that protein expression of FATPs, FABPs, and perilipin-2 in human placenta is decreased and placental lipid content and incorporation into lipid classes are reduced in IUGR. Placental tissue of idiopathic IUGR (n=25) and gestational age-matched, appropriately grown for gestational age (AGA) fetuses (n=19) was collected. We determined protein expression of FABP4 and perilipin-2 in placental homogenate and FATPs (2, 4, 6, CD36) in syncytiotrophoblast microvillous plasma membrane (MVM) by Western blot. Lipid droplet area (Oil Red O stain) and cellular FA content (GC/MS) were measured in chorionic villous tissue. MVM expression of FATP6 and CD36 was significantly increased in IUGR. The concentrations of seven n-6 and n-3 species long chain polyunsaturated FAs (LCPUFA) were significantly increased in the triglyceride fraction in IUGR vs AGA placenta. In summary, MVM FATP6 and CD36 protein expression is increased and LCPUFA are preferentially routed toward cellular storage in TG in the IUGR placenta, possibly to protect against oxidative stress associated with cellular FA accumulation. We speculate that these changes may be caused by impaired efflux of FA across the fetal-facing syncytiotrophoblast basal plasma membrane in IUGR placenta.
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