1
|
Larson AC, De Bie FR, Chang J, Davey MG, Flake AW. The EXTrauterine Environment for Neonatal Development: Present and Future. Pediatr Dev Pathol 2022; 25:253-262. [PMID: 35102770 DOI: 10.1177/10935266211067110] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Despite advances in clinical care and modest improvement in mortality rates for extreme prematurity, morbidity remains a significant challenge. The ideal environment to support prematurity would be fluidic and rely on natural fetal circulation to mimic the natural fetal amniotic environment, yet such an environment has been unsuccessful in long-term support until recently. Our group has succeeded in developing such a support system to foster fetal growth in the premature lamb model that shows promise for clinical translation. Here, we describe the EXTrauterine Environment for Neonatal Development (EXTEND) from its conception onwards, review published literature on fetal development and support of the premature lamb model in EXTEND, and discuss future applications.
Collapse
Affiliation(s)
- Abby C Larson
- Center for Fetal Research, 6567Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Felix R De Bie
- Center for Fetal Research, 6567Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Jonathan Chang
- Center for Fetal Research, 6567Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Marcus G Davey
- Center for Fetal Research, 6567Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Alan W Flake
- Center for Fetal Research, 6567Children's Hospital of Philadelphia, Philadelphia, PA, USA
| |
Collapse
|
2
|
Pendleton AL, Wesolowski SR, Regnault TRH, Lynch RM, Limesand SW. Dimming the Powerhouse: Mitochondrial Dysfunction in the Liver and Skeletal Muscle of Intrauterine Growth Restricted Fetuses. Front Endocrinol (Lausanne) 2021; 12:612888. [PMID: 34079518 PMCID: PMC8165279 DOI: 10.3389/fendo.2021.612888] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 04/22/2021] [Indexed: 11/14/2022] Open
Abstract
Intrauterine growth restriction (IUGR) of the fetus, resulting from placental insufficiency (PI), is characterized by low fetal oxygen and nutrient concentrations that stunt growth rates of metabolic organs. Numerous animal models of IUGR recapitulate pathophysiological conditions found in human fetuses with IUGR. These models provide insight into metabolic dysfunction in skeletal muscle and liver. For example, cellular energy production and metabolic rate are decreased in the skeletal muscle and liver of IUGR fetuses. These metabolic adaptations demonstrate that fundamental processes in mitochondria, such as substrate utilization and oxidative phosphorylation, are tempered in response to low oxygen and nutrient availability. As a central metabolic organelle, mitochondria coordinate cellular metabolism by coupling oxygen consumption to substrate utilization in concert with tissue energy demand and accretion. In IUGR fetuses, reducing mitochondrial metabolic capacity in response to nutrient restriction is advantageous to ensure fetal survival. If permanent, however, these adaptations may predispose IUGR fetuses toward metabolic diseases throughout life. Furthermore, these mitochondrial defects may underscore developmental programming that results in the sequela of metabolic pathologies. In this review, we examine how reduced nutrient availability in IUGR fetuses impacts skeletal muscle and liver substrate catabolism, and discuss how enzymatic processes governing mitochondrial function, such as the tricarboxylic acid cycle and electron transport chain, are regulated. Understanding how deficiencies in oxygen and substrate metabolism in response to placental restriction regulate skeletal muscle and liver metabolism is essential given the importance of these tissues in the development of later lifer metabolic dysfunction.
Collapse
Affiliation(s)
- Alexander L. Pendleton
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Stephanie R. Wesolowski
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, United States
| | | | - Ronald M. Lynch
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Sean W. Limesand
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| |
Collapse
|
3
|
Counter-directed leucine gradient promotes amino acid transfer across the human placenta. J Nutr Biochem 2021; 96:108760. [PMID: 33964466 DOI: 10.1016/j.jnutbio.2021.108760] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 02/04/2021] [Accepted: 04/16/2021] [Indexed: 02/01/2023]
Abstract
The developing fetus is highly vulnerable to imbalances in the supply of essential amino acids (AA). Transplacental AA transfer depends on complex interactions between accumulative transporters, exchangers and facilitators, which maintain both intra-extracellular and materno-fetal substrate gradients. We determined physiological AA gradients between maternal and fetal blood and assessed their importance by studying maternal-fetal leucine transfer in human trophoblasts. Maternal-venous and corresponding fetal-arterial/fetal-venous sera were collected from 22 healthy patients at partum. The acquisition of the full AA spectra in serum was performed by ion exchange chromatography. Physiological materno-fetal AA levels were evaluated using paired two-way ANOVA with Tukey's correction. AA concentrations and gradients were tested for associations with anthropometric data by Spearman correlation analysis. Functional effects of a physiological leucine gradient versus equimolar concentrations were tested in BeWo cells using L-[3H]-leucine in conventional and Transwell-based uptake and transfer experiments. The LAT1/SLC7A5-specific inhibitor JPH203 was used to evaluate LAT1-transporter-mediated leucine transport. Maternal AA concentrations correlated with preconceptional and maternal weights at partum. Interestingly, low materno-fetal AA gradients were associated with maternal weight, BMI and gestational weight gain. Leucine uptake was promoted by increased extracellular substrate concentrations. Materno-fetal leucine transfer was significantly increased against a 137µM leucine gradient demonstrating that transplacental leucine transport is stimulated by a counter-directed gradient. Moreover, leucine transfer was inhibited by 10µM JPH203 confirming that Leu transport across the trophoblast monolayer is LAT1-dependent. This study demonstrates a currently underestimated effect of transplacental AA gradients on efficient leucine transfer which could severely affect fetal development.
Collapse
|
4
|
Rozance PJ, Jones AK, Bourque SL, D'Alessandro A, Hay WW, Brown LD, Wesolowski SR. Effects of chronic hyperinsulinemia on metabolic pathways and insulin signaling in the fetal liver. Am J Physiol Endocrinol Metab 2020; 319:E721-E733. [PMID: 32830555 PMCID: PMC7864241 DOI: 10.1152/ajpendo.00323.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The effect of chronic of hyperinsulinemia in the fetal liver is poorly understood. Here, we produced hyperinsulinemia with euglycemia for ∼8 days in fetal sheep [hyperinsulinemic (INS)] at 0.9 gestation. INS fetuses had increased insulin and decreased oxygen and amino acid (AA) concentrations compared with saline-infused fetuses [control (CON)]. Glucose (whole body) utilization rates were increased, as expected, in INS fetuses. In the liver, however, there were few differences in genes and metabolites related to glucose and lipid metabolism and no activation of insulin signaling proteins (Akt and mTOR). There was increased p-AMPK activation and decreased mitochondrial mass (PGC1A expression, mitochondrial DNA content) in INS livers. Using an unbiased multivariate analysis with 162 metabolites, we identified effects on AA and one-carbon metabolism in the INS liver. Expression of the transaminase BCAT2 and glutaminase genes GLS1 and GLS2 was decreased, supporting decreased AA utilization. We further evaluated the roles of hyperinsulinemia and hypoxemia, both present in INS fetuses, on outcomes in the liver. Expression of PGC1A correlated only with hyperinsulinemia, p-AMPK correlated only with hypoxemia, and other genes and metabolites correlated with both hyperinsulinemia and hypoxemia. In fetal hepatocytes, acute treatment with insulin activated p-Akt and decreased PGC1A, whereas hypoxia activated p-AMPK. Overall, chronic hyperinsulinemia produced greater effects on amino acid metabolism compared with glucose and lipid metabolism and a novel effect on one-carbon metabolism in the fetal liver. These hepatic metabolic responses may result from the downregulation of insulin signaling and antagonistic effects of hypoxemia-induced AMPK activation that develop with chronic hyperinsulinemia.
Collapse
Affiliation(s)
- Paul J Rozance
- Perinatal Research Center, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Amanda K Jones
- Perinatal Research Center, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Stephanie L Bourque
- Perinatal Research Center, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Angelo D'Alessandro
- Perinatal Research Center, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - William W Hay
- Perinatal Research Center, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Laura D Brown
- Perinatal Research Center, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Stephanie R Wesolowski
- Perinatal Research Center, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| |
Collapse
|
5
|
Gevi F, Meloni A, Mereu R, Lelli V, Chiodo A, Ragusa A, Timperio AM. Urine Metabolome during Parturition. Metabolites 2020; 10:metabo10070290. [PMID: 32708819 PMCID: PMC7407522 DOI: 10.3390/metabo10070290] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 06/30/2020] [Accepted: 07/14/2020] [Indexed: 12/19/2022] Open
Abstract
In recent years, some studies have described metabolic changes during human childbirth labor. Metabolomics today is recognized as a powerful approach in a prenatal research context, since it can provide detailed information during pregnancy and it may enable the identification of biomarkers with potential diagnostic or predictive. This is an observational, longitudinal, prospective cohort study of a total of 51 serial urine samples from 15 healthy pregnant women, aged 29–40 years, which were collected before the onset of labor (out of labor, OL). In the same women, during labor (in labor or dilating phase, IL-DP). Samples were analyzed by hydrophilic interaction ultra-performance liquid chromatography coupled with mass spectrometry (HILIC-UPLC-MS), a highly sensitive, accurate, and unbiased approach. Metabolites were then subjected to multivariate statistical analysis and grouped by metabolic pathway. This method was used to identify the potential biomarkers. The top 20 most discriminative metabolites contributing to the complete separation of OL and IL-DP were identified. Urinary metabolites displaying the largest differences between OL and IL-DP belonged to steroid hormone, particularly conjugated estrogens and amino acids much of this difference is determined by the fetal contribution. In addition, our results highlighted the efficacy of using urine samples instead of more invasive techniques to evaluate the difference in metabolic analysis between OL and IL-DP.
Collapse
Affiliation(s)
- Federica Gevi
- Department of Biology and Ecology University of Tuscia, 01100 Viterbo, Italy; (F.G.); (V.L.)
| | - Alessandra Meloni
- Neonatal Department, Obstetrics and Gynecology Unit, Azienda Ospedaliera Universitaria (AOU), 09124 Cagliari, Italy; (A.M.); (R.M.); (A.C.)
| | - Rossella Mereu
- Neonatal Department, Obstetrics and Gynecology Unit, Azienda Ospedaliera Universitaria (AOU), 09124 Cagliari, Italy; (A.M.); (R.M.); (A.C.)
| | - Veronica Lelli
- Department of Biology and Ecology University of Tuscia, 01100 Viterbo, Italy; (F.G.); (V.L.)
| | - Antonella Chiodo
- Neonatal Department, Obstetrics and Gynecology Unit, Azienda Ospedaliera Universitaria (AOU), 09124 Cagliari, Italy; (A.M.); (R.M.); (A.C.)
| | - Antonio Ragusa
- Department of Obstetrics and Gynecology, Ospedale San Giovanni Calibita, Fatebenefratelli, Isola Tiberina, Via di Ponte Quattro Capi, 39, 00186 Roma, Italy;
| | - Anna Maria Timperio
- Department of Biology and Ecology University of Tuscia, 01100 Viterbo, Italy; (F.G.); (V.L.)
- Correspondence:
| |
Collapse
|
6
|
Alqurashi S, English S, Wall R. Nutritional requirements for reproduction and survival in the blowfly Lucilia sericata. MEDICAL AND VETERINARY ENTOMOLOGY 2020; 34:207-214. [PMID: 31846089 DOI: 10.1111/mve.12425] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 10/31/2019] [Accepted: 11/25/2019] [Indexed: 06/10/2023]
Abstract
Insects with access to finite energy resources must allocate these between maintenance and reproduction in a way that maximizes fitness. This will be influenced by a range of life-history characteristics and the environment in which any particular insect species lives. In the present study, females of the blowfly Lucilia sericata (Diptera: Calliphoridae) were fed diets differing in protein and carbohydrate (sucrose) content and the allocation of lipid to reproduction was quantified using a spectrophotometric method of analysis. Immediately after adult emergence, total body lipid, scaled for differences in body size, showed an initial decline as it was utilized to meet the metabolic demands of cuticle deposition, muscle maturation and then flight. When flies were denied access to sucrose, stored lipid then continued to decrease until flies died, usually within 4 days of emergence. However, flies given access to sucrose were able to increase body lipid content, demonstrating that carbohydrate is essential for homeostasis and that it can be used to synthesize lipid. Nevertheless, female flies fed sucrose only were unable to synthesize egg yolk. Only flies provided with protein were able to mature eggs. However, the rate of egg maturation and number and size of eggs matured were greater for female flies given liver compared with flies provided with pure whey protein powder. The results demonstrate the importance of different dietary components for different elements of the life-history of L. sericata, namely survival and reproduction.
Collapse
Affiliation(s)
- S Alqurashi
- School of Biological Sciences, University of Bristol, Bristol, U.K
- Faculty of Sciences, Department of Biology, University of Jeddah, Jeddah, Saudi Arabia
| | - S English
- School of Biological Sciences, University of Bristol, Bristol, U.K
| | - R Wall
- School of Biological Sciences, University of Bristol, Bristol, U.K
| |
Collapse
|
7
|
Partridge EA, Davey MG, Hornick MA, McGovern PE, Mejaddam AY, Vrecenak JD, Mesas-Burgos C, Olive A, Caskey RC, Weiland TR, Han J, Schupper AJ, Connelly JT, Dysart KC, Rychik J, Hedrick HL, Peranteau WH, Flake AW. An extra-uterine system to physiologically support the extreme premature lamb. Nat Commun 2017; 8:15112. [PMID: 28440792 PMCID: PMC5414058 DOI: 10.1038/ncomms15112] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 03/02/2017] [Indexed: 12/18/2022] Open
Abstract
In the developed world, extreme prematurity is the leading cause of neonatal mortality and morbidity due to a combination of organ immaturity and iatrogenic injury. Until now, efforts to extend gestation using extracorporeal systems have achieved limited success. Here we report the development of a system that incorporates a pumpless oxygenator circuit connected to the fetus of a lamb via an umbilical cord interface that is maintained within a closed 'amniotic fluid' circuit that closely reproduces the environment of the womb. We show that fetal lambs that are developmentally equivalent to the extreme premature human infant can be physiologically supported in this extra-uterine device for up to 4 weeks. Lambs on support maintain stable haemodynamics, have normal blood gas and oxygenation parameters and maintain patency of the fetal circulation. With appropriate nutritional support, lambs on the system demonstrate normal somatic growth, lung maturation and brain growth and myelination.
Collapse
Affiliation(s)
- Emily A Partridge
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Marcus G Davey
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Matthew A Hornick
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Patrick E McGovern
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Ali Y Mejaddam
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Jesse D Vrecenak
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Carmen Mesas-Burgos
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Aliza Olive
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Robert C Caskey
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Theodore R Weiland
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Jiancheng Han
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Alexander J Schupper
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - James T Connelly
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Kevin C Dysart
- Division of Neonatology, Department of Pediatrics, The Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Jack Rychik
- Division of Cardiology, Department of Pediatrics, The Children's Hospital of Philadelphia, 3401 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Holly L Hedrick
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - William H Peranteau
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Alan W Flake
- Center for Fetal Research, Department of Surgery, The Children's Hospital of Philadelphia Research Institute, Room 1116B, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| |
Collapse
|
8
|
Houin SS, Rozance PJ, Brown LD, Hay WW, Wilkening RB, Thorn SR. Coordinated changes in hepatic amino acid metabolism and endocrine signals support hepatic glucose production during fetal hypoglycemia. Am J Physiol Endocrinol Metab 2015; 308:E306-14. [PMID: 25516551 PMCID: PMC4329495 DOI: 10.1152/ajpendo.00396.2014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Reduced fetal glucose supply, induced experimentally or as a result of placental insufficiency, produces an early activation of fetal glucose production. The mechanisms and substrates used to fuel this increased glucose production rate remain unknown. We hypothesized that in response to hypoglycemia, induced experimentally with maternal insulin infusion, the fetal liver would increase uptake of lactate and amino acids (AA), which would combine with hormonal signals to support hepatic glucose production. To test this hypothesis, metabolic studies were done in six late gestation fetal sheep to measure hepatic glucose and substrate flux before (basal) and after [days (d)1 and 4] the start of hypoglycemia. Maternal and fetal glucose concentrations decreased by 50% on d1 and d4 (P < 0.05). The liver transitioned from net glucose uptake (basal, 5.1 ± 1.5 μmol/min) to output by d4 (2.8 ± 1.4 μmol/min; P < 0.05 vs. basal). The [U-¹³C]glucose tracer molar percent excess ratio across the liver decreased over the same period (basal: 0.98 ± 0.01, vs. d4: 0.89 ± 0.01, P < 0.05). Total hepatic AA uptake, but not lactate or pyruvate uptake, increased by threefold on d1 (P < 0.05) and remained elevated throughout the study. This AA uptake was driven largely by decreased glutamate output and increased glycine uptake. Fetal plasma concentrations of insulin were 50% lower, while cortisol and glucagon concentrations increased 56 and 86% during hypoglycemia (P < 0.05 for basal vs. d4). Thus increased hepatic AA uptake, rather than pyruvate or lactate uptake, and decreased fetal plasma insulin and increased cortisol and glucagon concentrations occur simultaneously with increased fetal hepatic glucose output in response to fetal hypoglycemia.
Collapse
Affiliation(s)
- Satya S Houin
- Perinatal Research Center, Department of Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, Colorado
| | - Paul J Rozance
- Perinatal Research Center, Department of Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, Colorado
| | - Laura D Brown
- Perinatal Research Center, Department of Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, Colorado
| | - William W Hay
- Perinatal Research Center, Department of Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, Colorado
| | - Randall B Wilkening
- Perinatal Research Center, Department of Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, Colorado
| | - Stephanie R Thorn
- Perinatal Research Center, Department of Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, Colorado
| |
Collapse
|
9
|
Arginyl-glutamine dipeptide or docosahexaenoic acid attenuate hyperoxia-induced lung injury in neonatal mice. Nutrition 2013; 28:1186-91. [PMID: 23044165 DOI: 10.1016/j.nut.2012.04.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 03/27/2012] [Accepted: 04/28/2012] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Supplementation studies of glutamine, arginine, and docosahexaenoic acid (DHA) have established the safety of each of these nutrients in neonates. However, the potential for a more stable and soluble dipeptide, arginyl-glutamine (Arg-Gln) or DHA, a long-chain ω-3 fatty acid with anti-inflammatory properties, to exert benefits on hyperoxia-induced lung injury has not to our knowledge been investigated. The aim of this study was to investigate whether Arg-Gln dipeptide or DHA could attenuate markers of injury and inflammation in neonatal mouse lungs exposed to hyperoxia. METHODS Seven-day-old mouse pups were placed with their dams in 75% oxygen for 5 d. After 5 d of hyperoxic exposure (postnatal days 7-12), pups were removed from hyperoxia and allowed to recover in atmospheric conditions for 5 d (postnatal days 12-17). Mouse pups received Arg-Gln (5 g · kg⁻¹ · d⁻¹) or DHA (5 g · kg⁻¹ · d⁻¹) or saline orally from postnatal days 12 through 17. Histologic changes, myeloperoxidase, lactate dehydrogenase, inflammatory cytokines, and nuclear factor-κB inhibitor levels were checked in each group. RESULTS The Arg-Gln and DHA prevented the development of key markers of injury, including histologic changes, myeloperoxidase, lactate dehydrogenase, and inflammatory cytokines interleukin-6 and C-X-C motif ligand 1 (CXCL1)/keratinocyte-derived chemokine (KC). The highly beneficial effects of Arg-Gln on the reversal of oxygen-induced lung damage was associated with restoration of levels of nuclear factor-κB inhibitor. CONCLUSION The Arg-Gln and DHA, with protective effects on hyperoxic lung injury in neonatal mice, are promising nutritional adjuncts that may prevent lung damage owing to oxygen toxicity in infants.
Collapse
|
10
|
Placental amino acids transport in intrauterine growth restriction. J Pregnancy 2012; 2012:972562. [PMID: 22997583 PMCID: PMC3401547 DOI: 10.1155/2012/972562] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 04/19/2012] [Indexed: 01/08/2023] Open
Abstract
The placenta represents a key organ for fetal growth as it acts as an interface between mother and fetus, regulating the fetal-maternal exchange of nutrients, gases, and waste products. During pregnancy, amino acids represent one of the major nutrients for fetal life, and both maternal and fetal concentrations are significantly different in pregnancies with intrauterine growth restriction when compared to uncomplicated pregnancies. The transport of amino acids across the placenta is a complex process that includes the influx of neutral, anionic, and cationic amino acids across the microvilluos plasma membrane of the syncytiotrophoblast, the passage through the cytoplasm of the trophoblasts, and the transfer outside the trophoblasts across the basal membrane into the fetal circulation. In this paper, we review the transport mechanisms of amino acids across the placenta in normal pregnancies and in pregnancies complicated by intrauterine growth restriction.
Collapse
|
11
|
Marconi AM, Mariotti V, Teng C, Ronzoni S, D'Amato B, Morabito A, Battaglia FC. Effect of antenatal betamethasone on maternal and fetal amino acid concentration. Am J Obstet Gynecol 2010; 202:166.e1-6. [PMID: 20022312 DOI: 10.1016/j.ajog.2009.10.704] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 07/19/2009] [Accepted: 10/07/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To determine the concentration of amino acids in women receiving the first course of antenatal betamethasone and to evaluate the umbilical venous and arterial amino acid concentrations at the time of elective cesarean section after betamethasone administration. STUDY DESIGN Blood samples were collected from 34 pregnant women at risk of premature delivery before and 24 and 48 hours after the first course of betamethasone. In addition, maternal and cord blood samples were collected in 13 women undergoing an elective cesarean section between 24 and 192 hours after betamethasone. RESULTS Maternal amino acid concentrations were significantly increased after the first dose of betamethasone. Overall total amino nitrogen increased 17.5% 24 hours after betamethasone administration and 20.5% after 48 hours. The concentration of most amino acids was increased both in the umbilical vein and artery after maternal betamethasone administration. CONCLUSION The concentration of maternal and fetal amino acids increases significantly after betamethasone administration.
Collapse
|
12
|
Abstract
Successful outcome of human pregnancy not only impacts the quality of infant life and well-being, but considerable evidence now suggests that what happens during fetal development may well impact health and well-being into adulthood. Consequently, a thorough understanding of the developmental events that occur between conception and delivery is needed. For obvious ethical reasons, many of the questions remaining about the progression of human pregnancy cannot be answered directly, necessitating the use of appropriate animal models. A variety of animal models exist for the study of both normal and compromised pregnancies, including laboratory rodents, non-human primates and domestic ruminants. While all of these animal models have merit, most suffer from the inability to repetitively sample from both the maternal and fetal side of the placenta, limiting their usefulness in the study of placental or fetal physiology under non-stressed in vivo conditions. No animal model truly recapitulates human pregnancy, yet the pregnant sheep has been used extensively to investigate maternal-fetal interactions. This is due in part to the ability to surgically place and maintain catheters in both the maternal and fetal vasculature, allowing repeated sampling from non-anesthetized pregnancies. Considerable insight has been gained on placental oxygen and nutrient transfer and utilization from use of pregnant sheep. These findings were often confirmed in human pregnancies once appropriate technologies became available. The purpose of this review is to provide an overview of human and sheep pregnancy, with emphasis placed on placental development and function as an organ of nutrient transfer.
Collapse
Affiliation(s)
- J S Barry
- Perinatal Research Facility, Department of Pediatrics, University of Colorado Health Sciences Center, Aurora, CO 80045-0508, USA
| | | |
Collapse
|
13
|
Waterman RC, Löest CA, Bryant WD, Petersen MK. Supplemental methionine and urea for gestating beef cows consuming low quality forage diets1. J Anim Sci 2007; 85:731-6. [PMID: 17060412 DOI: 10.2527/jas.2006-425] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A study was conducted to evaluate Met requirements of late-gestation beef cows consuming low quality forages on the premise that inadequate supply of metabolizable AA may limit protein accretion during pregnancy. Five ruminally cannulated, multiparous late-gestation beef cows (490 +/- 27 kg), of predominantly Angus (> or =75%) with Hereford and Simmental breeding, were used in a 5 x 5 Latin square experiment to evaluate the effects of postruminal dl-Met supplementation on N retention, serum metabolites, and plasma AA concentrations during the third trimester of pregnancy. The basal diet was fed individually, and weights of refusals were recorded for N intake determination. Treatments consisted of no urea, urea (0.053 +/- 0.002 g/kg of BW daily), urea + 5 g of Met/d, urea + 10 g of Met/d, and urea + 15 g of Met/d. Cows were adapted to the experimental diet 30 d before the beginning of the study, with periods lasting for 14 d; 4 d to allow for clearance of the previous treatment effects, 4 d for adaptation to the treatments, and 6 d for total fecal and urine collection. Blood samples were collected every 4 h on d 13 of each period for analysis of serum metabolites and plasma AA. Inclusion of urea increased DM and OM intakes (urea vs. no urea; P = 0.05), but no further improvement in intake was observed with inclusion of Met. Serum urea concentrations increased with inclusion of urea (P = 0.03) and responded quadratically (P = 0.06) when Met was added, with the lowest concentration observed in the urea + 5 g of Met/d treatment. More N was retained with the inclusion of urea (P = 0.04), and N retention increased linearly (P = 0.07) with inclusion of Met. Plasma Met concentration increased linearly (P < 0.01) with inclusion of Met. These data suggest that Met was a limiting AA and that supplementation of a combination of urea and 5 g/d of rumen-protected Met to low quality, forage diets will improve N retention and promote protein accretion during late pregnancy.
Collapse
Affiliation(s)
- R C Waterman
- Department of Animal and Range Sciences, New Mexico State University, Las Cruces, NM 88003, USA.
| | | | | | | |
Collapse
|
14
|
Teng C, Battaglia FC, Meschia G, Narkewicz MR, Wilkening RB. Fetal hepatic and umbilical uptakes of glucogenic substrates during a glucagon-somatostatin infusion. Am J Physiol Endocrinol Metab 2002; 282:E542-50. [PMID: 11832355 DOI: 10.1152/ajpendo.00248.2001] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To test the hypothesis that fetal hepatic glutamate output diverts the products of hepatic amino acid metabolism from hepatic gluconeogenesis, ovine fetal hepatic and umbilical uptakes of glucose and glucogenic substrates were measured before and during fetal glucagon-somatostatin (GS) infusion and during the combined infusion of GS, alanine, glutamine, and arginine. Before the infusions, hepatic uptake of lactate, alanine, glutamine, arginine, and other substrates was accompanied by hepatic output of pyruvate, aspartate, serine, glutamate, and ornithine. The GS infusion induced hepatic output of 1.00 +/- 0.07 mol glucose carbon/mol O(2) uptake, an equivalent reduction in hepatic output of pyruvate and glutamate carbon, a decrease in umbilical glucose uptake and placental uptake of fetal glutamate, an increase in hepatic alanine and arginine clearances, and a decrease in umbilical alanine, glutamine, and arginine uptakes. The latter result suggests that glucagon inhibits umbilical amino acid uptake. We conclude that fetal hepatic pyruvate and glutamate output is part of an adaptation to placental function that requires the fetal liver to maintain both a high rate of catabolism of glucogenic substrates and a low rate of gluconeogenesis.
Collapse
Affiliation(s)
- Cecilia Teng
- Departments of Pediatrics and Physiology, University of Colorado School of Medicine, Aurora, Colorado, 80045-0508, USA
| | | | | | | | | |
Collapse
|
15
|
Nakanishi T, Kekuda R, Fei YJ, Hatanaka T, Sugawara M, Martindale RG, Leibach FH, Prasad PD, Ganapathy V. Cloning and functional characterization of a new subtype of the amino acid transport system N. Am J Physiol Cell Physiol 2001; 281:C1757-68. [PMID: 11698233 DOI: 10.1152/ajpcell.2001.281.6.c1757] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have cloned a new subtype of the amino acid transport system N2 (SN2 or second subtype of system N) from rat brain. Rat SN2 consists of 471 amino acids and belongs to the recently identified glutamine transporter gene family that consists of system N and system A. Rat SN2 exhibits 63% identity with rat SN1. It also shows considerable sequence identity (50-56%) with the members of the amino acid transporter A subfamily. In the rat, SN2 mRNA is most abundant in the liver but is detectable in the brain, lung, stomach, kidney, testis, and spleen. When expressed in Xenopus laevis oocytes and in mammalian cells, rat SN2 mediates Na(+)-dependent transport of several neutral amino acids, including glycine, asparagine, alanine, serine, glutamine, and histidine. The transport process is electrogenic, Li(+) tolerant, and pH sensitive. The transport mechanism involves the influx of Na(+) and amino acids coupled to the efflux of H(+), resulting in intracellular alkalization. Proline, alpha-(methylamino)isobutyric acid, and anionic and cationic amino acids are not recognized by rat SN2.
Collapse
Affiliation(s)
- T Nakanishi
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Novak D, Quiggle F, Artime C, Beveridge M. Regulation of glutamate transport and transport proteins in a placental cell line. Am J Physiol Cell Physiol 2001; 281:C1014-22. [PMID: 11502579 DOI: 10.1152/ajpcell.2001.281.3.c1014] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We utilized HRP.1 cells derived from midgestation rat placental labyrinth to determine that the primary pathway for glutamate uptake is via system X, a Na(+)-dependent transport system. Kinetic parameters of system X activity were similar to those previously determined in rat and human placental membrane vesicle preparations. Amino acid depletion caused a significant upregulation of system X activity at 6, 24, and 48 h. This increase was reversed by the addition of glutamate and aspartate but not by the addition of alpha-(methylamino)isobutyric acid. Immunoblot analysis of the three transport proteins previously associated with system X activity indicated a trend toward an increase in GLT1, EAAC1, and GLAST1 immunoreactive protein contents by 48 h; cell surface expression of the same was enhanced by 24 h. Inhibition analysis suggested key roles for EAAC1 and GLAST1 in basal anionic amino acid transfer, with an enhanced role for GLT1 under conditions of amino acid depletion. In summary, amino acid availability as well as intracellular metabolism regulate anionic amino acid uptake into this placental cell line.
Collapse
Affiliation(s)
- D Novak
- Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida 32610, USA.
| | | | | | | |
Collapse
|
17
|
Paolini CL, Meschia G, Fennessey PV, Pike AW, Teng C, Battaglia FC, Wilkening RB. An in vivo study of ovine placental transport of essential amino acids. Am J Physiol Endocrinol Metab 2001; 280:E31-9. [PMID: 11120656 DOI: 10.1152/ajpendo.2001.280.1.e31] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Under normal physiological conditions, essential amino acids (EA) are transported from mother to fetus at different rates. The mechanisms underlying these differences include the expression of several amino acid transport systems in the placenta and the regulation of EA concentrations in maternal and fetal plasma. To study the relation of EA transplacental flux to maternal plasma concentration, isotopes of EA were injected into the circulation of pregnant ewes. Measurements of concentration and molar enrichment in maternal and fetal plasma and of umbilical plasma flow were used to calculate the ratio of transplacental pulse flux to maternal concentration (clearance) for each EA. Five EA (Met, Phe, Leu, Ile, and Val) had relatively high and similar clearances and were followed, in order of decreasing clearance, by Trp, Thr, His, and Lys. The five high-clearance EA showed strong correlation (r(2) = 0.98) between the pulse flux and maternal concentration. The study suggests that five of the nine EA have similar affinity for a rate-limiting placental transport system that mediates rapid flux from mother to fetus, and that differences in transport rates within this group of EA are determined primarily by differences in maternal plasma concentration.
Collapse
Affiliation(s)
- C L Paolini
- Department of Obstetrics and Gynecology, Dipartimento di Medicina Chirurgia e Odontoiatria San Paolo, University of Milano, 20142 Milano, Italy
| | | | | | | | | | | | | |
Collapse
|
18
|
Bellotti M, Pennati G, De Gasperi C, Battaglia FC, Ferrazzi E. Role of ductus venosus in distribution of umbilical blood flow in human fetuses during second half of pregnancy. Am J Physiol Heart Circ Physiol 2000; 279:H1256-63. [PMID: 10993792 DOI: 10.1152/ajpheart.2000.279.3.h1256] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Color Doppler sonography was used to study umbilical and ductus venosus (DV) flow in 137 normal fetuses between 20 and 38 wk of gestation. Hepatic flows were also evaluated. In all parts of the venous circulation examined, blood flow increased significantly with advancing gestational age. The weight-specific amniotic umbilical flow did not change significantly during gestation (120 +/- 44 ml. min(-1). kg(-1)), whereas DV flow decreased significantly (from 60 to 17 ml. min(-1). kg(-1)). The percentage of umbilical blood flow shunted through the DV decreased significantly (from 40% to 15%); consequently, the percentage of flow to the liver increased. The right lobe flow changed from 20 to 45%, whereas the left lobe flow was approximately constant (40%). These changes are related to different patterns of growth of the umbilical veins and DV diameters. The present data support the hypothesis that the DV plays a less important role in shunting well-oxygenated blood to the brain and myocardium in late normal pregnancy than in early gestation, which leads to increased fetal liver perfusion.
Collapse
MESH Headings
- Blood Flow Velocity/physiology
- Female
- Fetal Weight
- Fetus/blood supply
- Gestational Age
- Humans
- Liver/blood supply
- Liver/diagnostic imaging
- Liver/embryology
- Liver Circulation/physiology
- Placental Circulation/physiology
- Pregnancy
- Pregnancy Trimester, Second/physiology
- Pregnancy Trimester, Third/physiology
- Reference Values
- Regression Analysis
- Ultrasonography, Doppler, Color
- Ultrasonography, Doppler, Pulsed
- Ultrasonography, Prenatal
- Umbilical Veins/diagnostic imaging
- Umbilical Veins/embryology
- Umbilical Veins/physiology
- Vena Cava, Inferior/diagnostic imaging
- Vena Cava, Inferior/embryology
- Vena Cava, Inferior/physiology
Collapse
Affiliation(s)
- M Bellotti
- Department of Obstetrics and Gynecology, University of Milan, 20142 Milan, Italy.
| | | | | | | | | |
Collapse
|
19
|
Timmerman M, Teng C, Wilkening RB, Fennessey P, Battaglia FC, Meschia G. Effect of dexamethasone on fetal hepatic glutamine-glutamate exchange. Am J Physiol Endocrinol Metab 2000; 278:E839-45. [PMID: 10780940 DOI: 10.1152/ajpendo.2000.278.5.e839] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Intravenous infusion of dexamethasone (Dex) in the fetal lamb causes a two- to threefold increase in plasma glutamine and other glucogenic amino acids and a decrease of plasma glutamate to approximately one-third of normal. To explore the underlying mechanisms, hepatic amino acid uptake and conversion of L-[1-(13)C]glutamine to L-[1-(13)C]glutamate and (13)CO(2) were measured in six sheep fetuses before and in the last 2 h of a 26-h Dex infusion. Dex decreased hepatic glutamine and alanine uptakes (P < 0.01) and hepatic glutamate output (P < 0.001). Hepatic outputs of the glutamate (R(Glu,Gln)) and CO(2) formed from plasma glutamine decreased to 21 (P < 0.001) and 53% (P = 0.009) of control, respectively. R(Glu,Gln), expressed as a fraction of both outputs, decreased (P < 0.001) from 0.36 +/- 0.02 to 0.18 +/- 0.04. Hepatic glucose output remained virtually zero throughout the experiment. We conclude that Dex decreases fetal hepatic glutamate output by increasing the routing of glutamate carbon into the citric acid cycle and by decreasing the hepatic uptake of glucogenic amino acids.
Collapse
Affiliation(s)
- M Timmerman
- Department of Obstetrics and Gynecology, Erasmus University, 3000 DR Rotterdam, The Netherlands
| | | | | | | | | | | |
Collapse
|
20
|
Townsend SF, Thureen PJ, Hay WW, Narkewicz MR. Development of primary culture of ovine fetal hepatocytes for studies of amino acid metabolism and insulinlike growth factors. In Vitro Cell Dev Biol Anim 1993; 29A:592-6. [PMID: 8354668 DOI: 10.1007/bf02634153] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We report the development and characterization of a system of primary culture of ovine fetal hepatocytes to aid in the understanding of the cellular regulation of fetal growth and metabolism with emphasis on amino acid metabolism and insulinlike growth factor gene expression and to allow comparison to in vivo studies. Hepatocytes were isolated from late gestation fetal lambs by in situ perfusion and collagenase digestion utilizing occlusion of the ductus venosus to limit intrahepatic shunting. Hepatocytes were cultured in media modified to mimic fetal concentrations of glucose, lactate, and amino acids. Ovine fetal hepatocytes in primary culture maintain the pattern of fetal amino acid production and utilization seen across the fetal liver in vivo. Specifically, there is a net production of serine and a net utilization of glycine. Cultured ovine fetal hepatocytes specifically increase tritiated thymidine incorporation in response to insulin and insulinlike growth factor II (IGF-II). IGF-II mRNA abundance is high and IGF-I mRNA is low in cultured ovine fetal hepatocytes as in the fetal sheep liver in vivo. These data demonstrate the successful isolation of ovine fetal hepatocytes that retain some of the characteristics of the ovine fetal liver while maintained in short-term culture.
Collapse
Affiliation(s)
- S F Townsend
- Department of Pediatrics, University of Colorado Health Sciences Center, Denver 80262
| | | | | | | |
Collapse
|
21
|
Carter BS, Moores RR, Battaglia FC. Placental transport and fetal and placental metabolism of amino acids. J Nutr Biochem 1991. [DOI: 10.1016/0955-2863(91)90041-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|