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Arora M, Mehndiratta M, Almeida EA, Kotru M, Gupta B. Gene expression of iron transporters, markers of vascularization and structural integrity in placenta of mothers with and without anemia. Mol Biol Rep 2024; 51:652. [PMID: 38734792 DOI: 10.1007/s11033-024-09609-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Accepted: 05/02/2024] [Indexed: 05/13/2024]
Abstract
OBJECTIVE To compare the mRNA expression of placental iron transporters (TfR-1 and FPN), markers of placental vascularization (VEGF and sFLT1) and marker of structural integrity (LMN-A) in term women with and without iron deficiency anemia. MATERIALS AND METHODS A total of 30 pregnant women were enrolled; 15 cases of iron deficiency anemia (Hb 7-10.9 gm/dL) and 15 gestational age matched healthy controls (Hb ≥ 11 gm/dL). Peripheral venous blood was collected for assessment of hemoglobin levels and serum iron profile. Placental tissue was used for assessing the mRNA expression of TfR-1, FPN, VEGF, sFLT-1 and LMN-A via real time PCR. RESULTS Placental expression of TfR-1, VEGF and LMN-A was increased in pregnant women with anemia compared to healthy pregnant controls. Placental expression of sFLT-1 was decreased in pregnant women with anemia compared to healthy pregnant controls. There was no change in the placental expression of FPN. CONCLUSION The increased expression of TfR-1, VEGF and LMN-A in cases of iron deficiency anemia are most likely to be compensatory in nature to help maintain adequate fetal iron delivery. WHAT DOES THIS STUDY ADDS TO THE CLINICAL WORK Compensatory changes in the placenta aimed at buffering transport of iron to the fetus are seen in pregnant women with anemia compared to healthy pregnant controls.
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Affiliation(s)
- Madhav Arora
- University College of Medical Sciences & GTB Hospital, University of Delhi, Delhi, India
| | - Mohit Mehndiratta
- Department of Biochemistry, University College of Medical Sciences & GTB Hospital, University of Delhi, Delhi, 110095, India.
| | - Edelbert Anthonio Almeida
- Department of Biochemistry, University College of Medical Sciences & GTB Hospital, University of Delhi, Delhi, 110095, India
| | - Mrinalini Kotru
- Department of Pathology, University College of Medical Sciences and GTB Hospital, University of Delhi, Delhi, India
| | - Bindiya Gupta
- Department of Obstetrics and Gynaecology, University College of Medical Sciences & GTB Hospital, University of Delhi, Delhi, India
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Barad A, Guillet R, Pressman EK, Katzman PJ, Ganz T, Nemeth E, O'Brien KO. Placental ferroportin protein abundance is associated with neonatal erythropoietic activity and iron status in newborns at high risk for iron deficiency and anemia. Am J Clin Nutr 2024; 119:76-86. [PMID: 37890671 PMCID: PMC10808842 DOI: 10.1016/j.ajcnut.2023.10.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/17/2023] [Accepted: 10/20/2023] [Indexed: 10/29/2023] Open
Abstract
BACKGROUND Murine data suggest that the placenta downregulates ferroportin (FPN) when iron is limited to prioritize iron for its own needs. Human data on the impact of maternal and neonatal iron status on placental FPN expression are conflicting. OBJECTIVES This study aimed to identify determinants of placental FPN protein abundance and to assess the utility of the placental iron deficiency index (PIDI) as a measure of maternal/fetal iron status in newborns at high risk for anemia. METHODS Placental FPN protein abundance was measured by western blots in placentae collected from 133 neonates born to adolescents (17.4 ± 1.1 y) carrying singletons (delivery gestational age [GA]: 39.9 ± 1.3 wk) and from 130 neonates born to 65 females (30.4 ± 5.2 y) carrying multiples (delivery GA: 35.0 ± 2.8 wk). Placental FPN and the PIDI (FPN:transferrin receptor 1) were evaluated in relation to neonatal and maternal iron-related markers (hemoglobin [Hb], serum ferritin [SF], soluble transferrin receptor [sTfR], total body iron [TBI], hepcidin, erythropoietin [EPO], erythroferrone). RESULTS FPN protein was detected in all placentae delivered between 25 and 42 wk GA. Placental FPN protein abundance was associated with neonatal iron and erythropoietic markers (EPO: β: 0.10; 95% confidence interval [CI]: 0.06, 0.35; sTfR: β: 0.20; 95% CI: 0.03, 0.18; hepcidin: β: -0.06; 95% CI: -0.13, -0.0003; all P < 0.05). Maternal sTfR was only indirectly associated with placental FPN, with neonatal sTfR as the mediator (β-indirect: 0.06; 95% CI; 0.03, 0.11; P = 0.003). The PIDI was associated with neonatal Hb (β: -0.02; 95% CI: -0.03, -0.003), EPO (β: 0.07; 95% CI: 0.01, 0.14), and sTfR (β: 0.13; 95% CI: 0.004, 0.3) and with maternal SF (β: 0.08, 95% CI: 0.02, 0.14), TBI (β: 0.02; 95% CI: 0.009, 0.04), EPO (β: -0.10; 95% CI: -0.19, -0.01), sTfR (β: -0.16: 95% CI: -0.27, -0.06), and hepcidin (β: 0.05; 95% CI: 0.002, 0.11) at delivery (all P < 0.05). CONCLUSIONS Placental FPN abundance was positively associated with neonatal indicators of increased erythropoietic activity and poor iron status. The PIDI was associated with maternal and neonatal iron-related markers but in opposite directions. More data are needed from a lower-risk normative group of females to assess the generalizability of findings. These trials were registered at clinicaltrials.gov as NCT01019902 and NCT01582802.
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Affiliation(s)
- Alexa Barad
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, United States
| | - Ronnie Guillet
- Department of Pediatrics, Neonatology, University of Rochester School of Medicine, Rochester, NY, United States
| | - Eva K Pressman
- Department of Obstetrics and Gynecology, University of Rochester School of Medicine, Rochester, NY, United States
| | - Philip J Katzman
- Department of Pathology and Clinical Laboratory Medicine, University of Rochester School of Medicine, Rochester, NY, United States
| | - Tomas Ganz
- Center for Iron Disorders, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, United States
| | - Elizabeta Nemeth
- Center for Iron Disorders, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, United States
| | - Kimberly O O'Brien
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, United States.
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Iron Metabolism and Ferroptosis in Physiological and Pathological Pregnancy. Int J Mol Sci 2022; 23:ijms23169395. [PMID: 36012659 PMCID: PMC9409111 DOI: 10.3390/ijms23169395] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 08/16/2022] [Accepted: 08/17/2022] [Indexed: 12/13/2022] Open
Abstract
Iron is a vital element in nearly every living organism. During pregnancy, optimal iron concentration is essential for both maternal health and fetal development. As the barrier between the mother and fetus, placenta plays a pivotal role in mediating and regulating iron transport. Imbalances in iron metabolism correlate with severe adverse pregnancy outcomes. Like most other nutrients, iron exhibits a U-shaped risk curve. Apart from iron deficiency, iron overload is also dangerous since labile iron can generate reactive oxygen species, which leads to oxidative stress and activates ferroptosis. In this review, we summarized the molecular mechanism and regulation signals of placental iron trafficking under physiological conditions. In addition, we revealed the role of iron metabolism and ferroptosis in the view of preeclampsia and gestational diabetes mellitus, which may bring new insight to the pathogenesis and treatment of pregnancy-related diseases.
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Barad A, Guillet R, Pressman EK, Katzman PJ, Miller RK, Darrah TH, O'Brien KO. Placental Iron Content Is Lower than Previously Estimated and Is Associated with Maternal Iron Status in Women at Greater Risk of Gestational Iron Deficiency and Anemia. J Nutr 2022; 152:737-746. [PMID: 34875094 DOI: 10.1093/jn/nxab416] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 10/14/2021] [Accepted: 12/03/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Based on limited data, it is estimated that the placenta retains 90 mg of iron. Little is known about determinants of placental iron content. Animal data indicate that the placenta prioritizes iron for its own needs, but this hypothesis has not been evaluated in humans. OBJECTIVES To characterize placental iron content and placental iron concentration (p[Fe]) in pregnant women at risk of iron insufficiency and identify determinants of p[Fe]. METHODS Placentas were collected from 132 neonates born to teens carrying singletons (≤18 y) and 101 neonates born to 48 women carrying multiples (20-46 y). Maternal and neonatal iron status indicators [hemoglobin, serum ferritin (SF), soluble transferrin receptor (sTfR), serum iron, total body iron (TBI)] and hormones (erythropoietin, hepcidin) were measured. p[Fe] was measured using inductively coupled plasma-mass spectrometry. Correlation analyses and mixed-effects models were constructed to identify determinants of p[Fe]. RESULTS Mean placental iron content was 23 mg per placenta (95% CI: 15, 33 mg) in the multiples and 40 mg (95% CI: 31, 51 mg) in the teens (P = 0.03). Mean p[Fe] did not differ between the cohorts. p[Fe] was higher in anemic (175 μg/g; 95% CI: 120, 254 μg/g) compared with nonanemic (46 μg/g; 95% CI: 26, 82 μg/g) women carrying multiples (P = 0.009), but did not differ between anemic (62 μg/g; 95% CI: 40, 102 μg/g) and nonanemic (73 μg/g; 95% CI: 56, 97 μg/g) teens. In women carrying multiples, low maternal iron status [lower SF (P = 0.002) and lower TBI (P = 0.01)] was associated with higher p[Fe], whereas in teens, improved iron status [lower sTfR (P = 0.03) and higher TBI (P = 0.03)] was associated with higher p[Fe]. CONCLUSIONS Placental iron content was ∼50% lower than previously estimated. p[Fe] is significantly associated with maternal iron status. In women carrying multiples, poor maternal iron status was associated with higher p[Fe], whereas in teens, improved iron status was associated with higher p[Fe]. More data are needed to understand determinants of p[Fe] and the variable iron partitioning in teens compared with mature women.
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Affiliation(s)
- Alexa Barad
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
| | - Ronnie Guillet
- Department of Pediatrics, Division of Neonatology, University of Rochester School of Medicine, Rochester, NY, USA
| | - Eva K Pressman
- Department of Obstetrics and Gynecology, University of Rochester School of Medicine, Rochester, NY, USA
| | - Philip J Katzman
- Department of Pathology and Clinical Laboratory Medicine, University of Rochester School of Medicine, Rochester, NY, USA
| | - Richard K Miller
- Department of Obstetrics and Gynecology, University of Rochester School of Medicine, Rochester, NY, USA.,Department of Pathology and Clinical Laboratory Medicine, University of Rochester School of Medicine, Rochester, NY, USA
| | - Thomas H Darrah
- School of Earth Science, The Ohio State University, Columbus, OH, USA.,Global Water Institute, The Ohio State University, Columbus, OH, USA
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O'Brien KO. Maternal, fetal and placental regulation of placental iron trafficking. Placenta 2021; 125:47-53. [PMID: 34974896 DOI: 10.1016/j.placenta.2021.12.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/15/2021] [Accepted: 12/21/2021] [Indexed: 12/26/2022]
Abstract
The human placenta is a highly specialized organ that is responsible for housing, protecting, and nourishing the fetus across gestation. The placenta is essential as it functions among other things as the liver, lungs, and gut while also playing key immunological and endocrine roles. The structure and transport capacity of this temporary organ must evolve as gestation progresses while also adapting to possible alterations in maternal nutrient availability. All nutrients needed by the developing fetus must cross the human placenta. Iron (Fe) is one such nutrient that is both integral to placental function and to successful pregnancy outcomes. Iron deficiency is among the most common nutrient deficiencies globally and pregnant women are particularly vulnerable. Data on the partitioning of Fe between the mother, placenta and fetus are evolving yet many unanswered questions remain. Hepcidin, erythroferrone and erythropoietin are regulatory hormones that are integral to iron homeostasis. The mother, fetus and placenta independently produce these hormones, but the relative function of these hormones varies in each of the maternal, placental, and fetal compartments. This review will summarize basic aspects of Fe physiology in pregnant women and the maternal, fetal, and placental adaptations that occur to maintain Fe homeostasis at this key life stage.
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Affiliation(s)
- Kimberly O O'Brien
- Division of Nutritional Sciences, Cornell University, 230 Savage Hall, Ithaca, NY, 14850, USA.
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Venkata Surekha M, Sujatha T, Gadhiraju S, Kotturu SK, Siva Prasad M, Sarada K, Bhaskar V, Uday Kumar P. Effect of Maternal Iron Deficiency Anaemia on the Expression of Iron Transport Proteins in the Third Trimester Placenta. Fetal Pediatr Pathol 2021; 40:581-596. [PMID: 32096669 DOI: 10.1080/15513815.2020.1725942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BackgroundDuring pregnancy, iron is transferred from mother to fetus with placental iron transport proteins (Transferrin receptor, Divalent metal transporter/DMT1, ferroportin/FPN1 and Zyklopen). The aim of the study was to evaluate the effect of maternal iron deficiency anemia on placental iron transporters. Study Design: Two hundred pregnant women, in third trimester of pregnancy were divided into anemic (Hemoglobin/Hb < 11g/dl) and non-anemic groups (Hb ≥ 11 g/dl). After delivery, placental expression of iron transport proteins were studied by immunohistochemistry and by mRNA analysis. Results: Of the 200 subjects, 59% were anemic. All 3 placental proteins showed statistically significant increase in immunohistochemical expression, proportionate to the severity of maternal anemia. The mRNA expression of DMT-1 gene was only significantly elevated in placentas of anemic mothers. Conclusion: Although in our study mRNA expression of only the DMT-1 gene was significantly high, immunohistochemically however all the 3 proteins showed significantly higher expression in placentas of anemic mothers.
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Affiliation(s)
| | - Thathapudi Sujatha
- Pathology and Microbiology Division, National Institute of Nutrition, Hyderabad, India
| | | | | | - Mudili Siva Prasad
- Biochemistry Division, National Institute of Nutrition, Hyderabad, India
| | - K Sarada
- Pathology and Microbiology Division, National Institute of Nutrition, Hyderabad, India
| | - Varanasi Bhaskar
- Statistics Division, National Institute of Nutrition, Hyderabad, India
| | - Putcha Uday Kumar
- Pathology and Microbiology Division, National Institute of Nutrition, Hyderabad, India
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Cao C, Prado MA, Sun L, Rockowitz S, Sliz P, Paulo JA, Finley D, Fleming MD. Maternal Iron Deficiency Modulates Placental Transcriptome and Proteome in Mid-Gestation of Mouse Pregnancy. J Nutr 2021; 151:1073-1083. [PMID: 33693820 PMCID: PMC8112763 DOI: 10.1093/jn/nxab005] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/26/2020] [Accepted: 01/06/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Maternal iron deficiency (ID) is associated with poor pregnancy and fetal outcomes. The effect is thought to be mediated by the placenta but there is no comprehensive assessment of placental responses to maternal ID. Additionally, whether the influence of maternal ID on the placenta differs by fetal sex is unknown. OBJECTIVES To identify gene and protein signatures of ID mouse placentas at mid-gestation. A secondary objective was to profile the expression of iron genes in mouse placentas across gestation. METHODS We used a real-time PCR-based array to determine the mRNA expression of all known iron genes in mouse placentas at embryonic day (E) 12.5, E14.5, E16.5, and E19.5 (n = 3 placentas/time point). To determine the effect of maternal ID, we performed RNA sequencing and proteomics in male and female placentas from ID and iron-adequate mice at E12.5 (n = 8 dams/diet). RESULTS In female placentas, 6 genes, including transferrin receptor (Tfrc) and solute carrier family 11 member 2, were significantly changed by maternal ID. An additional 154 genes were altered in male ID placentas. A proteomic analysis quantified 7662 proteins in the placenta. Proteins translated from iron-responsive element (IRE)-containing mRNA were altered in abundance; ferritin and ferroportin 1 decreased, while TFRC increased in ID placentas. Less than 4% of the significantly altered genes in ID placentas occurred both at the transcriptional and translational levels. CONCLUSIONS Our data demonstrate that the impact of maternal ID on placental gene expression in mice is limited in scope and magnitude at mid-gestation. We provide strong evidence for IRE-based transcriptional and translational coordination of iron gene expression in the mouse placenta. Finally, we discover sexually dimorphic effects of maternal ID on placental gene expression, with more genes and pathways altered in male compared with female mouse placentas.
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Affiliation(s)
- Chang Cao
- Address correspondence to CC (e-mail: )
| | - Miguel A Prado
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Liang Sun
- Computational Health Informatics Program, Boston Children's Hospital, Boston, MA, USA,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, USA
| | - Shira Rockowitz
- Computational Health Informatics Program, Boston Children's Hospital, Boston, MA, USA,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, USA
| | - Piotr Sliz
- Computational Health Informatics Program, Boston Children's Hospital, Boston, MA, USA,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, USA,Division of Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
| | - Joao A Paulo
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Daniel Finley
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Mark D Fleming
- Department of Pathology, Boston Children's Hospital, Boston, MA, USA
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Sangkhae V, Fisher AL, Wong S, Koenig MD, Tussing-Humphreys L, Chu A, Lelić M, Ganz T, Nemeth E. Effects of maternal iron status on placental and fetal iron homeostasis. J Clin Invest 2020; 130:625-640. [PMID: 31661462 DOI: 10.1172/jci127341] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 10/22/2019] [Indexed: 12/14/2022] Open
Abstract
Iron deficiency is common worldwide and is associated with adverse pregnancy outcomes. The increasing prevalence of indiscriminate iron supplementation during pregnancy also raises concerns about the potential adverse effects of iron excess. We examined how maternal iron status affects the delivery of iron to the placenta and fetus. Using mouse models, we documented maternal homeostatic mechanisms that protect the placenta and fetus from maternal iron excess. We determined that under physiological conditions or in iron deficiency, fetal and placental hepcidin did not regulate fetal iron endowment. With maternal iron deficiency, critical transporters mediating placental iron uptake (transferrin receptor 1 [TFR1]) and export (ferroportin [FPN]) were strongly regulated. In mice, not only was TFR1 increased, but FPN was surprisingly decreased to preserve placental iron in the face of fetal iron deficiency. In human placentas from pregnancies with mild iron deficiency, TFR1 was increased, but there was no change in FPN. However, induction of more severe iron deficiency in human trophoblast in vitro resulted in the regulation of both TFR1 and FPN, similar to what was observed in the mouse model. This placental adaptation that prioritizes placental iron is mediated by iron regulatory protein 1 (IRP1) and is important for the maintenance of mitochondrial respiration, thus ultimately protecting the fetus from the potentially dire consequences of generalized placental dysfunction.
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Affiliation(s)
| | - Allison L Fisher
- Center for Iron Disorders, Department of Medicine, and.,Molecular, Cellular and Integrative Physiology Graduate Program, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Shirley Wong
- Center for Iron Disorders, Department of Medicine, and
| | - Mary Dawn Koenig
- Department of Women's, Children's and Family Health Science, College of Nursing
| | - Lisa Tussing-Humphreys
- Division of Academic Internal Medicine, Department of Medicine, and.,Institute for Health Research and Policy, University of Illinois at Chicago (UIC), Chicago, Illinois, USA
| | - Alison Chu
- Department of Pediatrics, Division of Neonatology and Developmental Biology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Melisa Lelić
- Medical Faculty, University of Tuzla, Tuzla, Bosnia and Herzegovina
| | - Tomas Ganz
- Center for Iron Disorders, Department of Medicine, and
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Differential Iron Status and Trafficking in Blood and Placenta of Anemic and Non-anemic Primigravida Supplemented with Daily and Weekly Iron Folic Acid Tablets. Indian J Clin Biochem 2020; 35:43-53. [PMID: 32071495 DOI: 10.1007/s12291-018-0794-2] [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: 08/02/2018] [Accepted: 09/25/2018] [Indexed: 10/28/2022]
Abstract
Abstract The molecular mechanism of iron transfer across placenta in response to maternal anemic status/ iron supplementation is not clear. We hypothesized that maternal iron/ anemia status during early trimesters can be utilized as a biomarker tool to get estimates of placental iron status. Early interventions can be envisaged to maintain optimum placental/ foetal iron levels for healthy pregnancy outcomes. One hundred twenty primigravida were recruited and divided into non-anemic and anemic group on the basis of hemoglobin levels. The groups were randomly allocated to receive daily and weekly iron folic acid (IFA) tablets till six weeks postpartum. Hematological and iron status markers in blood and placenta were studied along with the delivery notes. Weekly IFA supplementation in anemic primigravidas resulted in significantly reduced levels of hematological markers (p < 0.01); whereas non-anemic primigravidas showed lower ferritin and iron levels, and higher soluble transferrin receptor levels (p < 0.05). At baseline, C-reactive protein and cortisol hormone levels were also significantly lower in non-anemic primigravidas (p < 0.05). A significantly decreased placental ferritin expression (p < 0.05); and an increased placental transferrin expression was seen in anemic primigravidas supplemented with weekly IFA tablets. A significant positive correlation was observed between serum and placental ferritin expression in anemic pregnant women (r = 0.80; p < 0.007). Infant weight, gestational length and placental weight were comparable in both the supplementation groups. To conclude, mother's serum iron / anemia status switches the modulation in placental iron transporter expression for delivering the optimum iron to the foetus for healthy pregnancy outcomes. Trial Registration Clinical Trial Registry-India: CTRI/2014/10/005135.
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10
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Sangkhae V, Nemeth E. Placental iron transport: The mechanism and regulatory circuits. Free Radic Biol Med 2019; 133:254-261. [PMID: 29981833 PMCID: PMC7059975 DOI: 10.1016/j.freeradbiomed.2018.07.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 06/30/2018] [Accepted: 07/03/2018] [Indexed: 02/06/2023]
Abstract
As the interface between the fetal and maternal circulation, the placenta facilitates both nutrient and waste exchange for the developing fetus. Iron is essential for healthy pregnancy, and transport of iron across the placenta is required for fetal growth and development. Perturbation of this transfer can lead to adverse pregnancy outcomes. Despite its importance, our understanding of how a large amount of iron is transported across placental membranes, how this process is regulated, and which iron transporter proteins function in different placental cells remains rudimentary. Mechanistic studies in mouse models, including placenta-specific deletion or overexpression of iron-related proteins will be essential to make progress. This review summarizes our current understanding about iron transport across the syncytiotrophoblast under physiological conditions and identifies areas for further investigation.
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Affiliation(s)
- Veena Sangkhae
- Center for Iron Disorders, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, 10833 LeConte Ave, CHS 37-131, Los Angeles, CA 90095, USA.
| | - Elizabeta Nemeth
- Center for Iron Disorders, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, 10833 LeConte Ave, CHS 37-131, Los Angeles, CA 90095, USA.
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11
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Glycosylation Profile of the Transferrin Receptor in Gestational Iron Deficiency and Early-Onset Severe Preeclampsia. J Pregnancy 2019; 2019:9514546. [PMID: 30854239 PMCID: PMC6378037 DOI: 10.1155/2019/9514546] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 12/01/2018] [Accepted: 01/15/2019] [Indexed: 12/14/2022] Open
Abstract
Objective To examine the expression of hypoxia-inducible factor-1α (HIF-1α), TfR1, and TfR1-attached terminal monosaccharides in placentas of women with IDAP and severe preeclampsia. Methods TfR1 and HIF-1α were detected by western blot. Immunoadsorption of TfR1 was performed to characterize the terminal monosaccharides by specific lectin binding. Results There was no difference in the expression of TfR1 and HIF-1α between groups. Lectin blot analysis pointed out an overexpression of galactose β1-4 N-acetylglucosamine (Gal-GlcNAc) and mannose in severe preeclampsia. Conclusion The increase in Gal-GlcNAc may be due to the increased presence of antennary structures and the mannose glycans of TfR1 may indicate the presence of misfolded or incomplete proteins. These findings may be associated with the low expression of placental TfR1 in women with preeclampsia.
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12
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Shah A, Mankus CI, Vermilya AM, Soheilian F, Clogston JD, Dobrovolskaia MA. Feraheme® suppresses immune function of human T lymphocytes through mitochondrial damage and mitoROS production. Toxicol Appl Pharmacol 2018; 350:52-63. [PMID: 29715466 DOI: 10.1016/j.taap.2018.04.028] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 04/19/2018] [Accepted: 04/20/2018] [Indexed: 12/31/2022]
Abstract
Despite attractive properties for both therapeutic and diagnostic applications, the clinical use of iron oxide nanoparticles (IONPs) is limited to iron replacement in severely anemic patient populations. While several studies have reported about the immunotoxicity of IONPs, the mechanisms of this toxicity are mostly unknown. We conducted a mechanistic investigation using an injectable form of IONP, Feraheme®. In the cultures of primary human T cells, Feraheme induced miotochondrial oxidative stress and resulted in changes in mitochondrial dynamics, architecture, and membrane potential. These molecular events were responsible for the decrease in cytokine production and proliferation of mitogen-activated T cells. The induction of mitoROS by T cells in response to Feraheme was insufficient to induce total redox imbalance at the cellular level. Consequently, we resolved this toxicity by the addition of the mitochondria-specific antioxidant MitoTEMPO. We further used these findings to develop an experimental framework consisting of critical assays that can be used to estimate IONP immunotoxicity. We explored this framework using several immortalized T-cell lines and found that none of them recapitulate the toxicity observed in the primary cells. Next, we compared the immunotoxicity of Feraheme to that of other FDA-approved iron-containing complex drug formulations and found that the mitochondrial damage and the resulting suppression of T-cell function are specific to Feraheme. The framework, therefore, can be used for comparing the immunotoxicity of Feraheme with that of its generic versions, while other iron-based complex drugs require case-specific mechanistic investigation.
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Affiliation(s)
- Ankit Shah
- Nanotechnology Characterization Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Cassandra I Mankus
- Nanotechnology Characterization Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Alison M Vermilya
- Nanotechnology Characterization Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Ferri Soheilian
- Electron Microscopy Laboratory, Leidos Biomedical Research, Inc, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Jeffrey D Clogston
- Nanotechnology Characterization Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Marina A Dobrovolskaia
- Nanotechnology Characterization Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA.
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Jobarteh ML, McArdle HJ, Holtrop G, Sise EA, Prentice AM, Moore SE. mRNA Levels of Placental Iron and Zinc Transporter Genes Are Upregulated in Gambian Women with Low Iron and Zinc Status. J Nutr 2017; 147:1401-1409. [PMID: 28515164 PMCID: PMC5483961 DOI: 10.3945/jn.116.244780] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/12/2017] [Accepted: 03/30/2017] [Indexed: 12/22/2022] Open
Abstract
Background: The role of the placenta in regulating micronutrient transport in response to maternal status is poorly understood. Objective: We investigated the effect of prenatal nutritional supplementation on the regulation of placental iron and zinc transport. Methods: In a randomized trial in rural Gambia [ENID (Early Nutrition and Immune Development)], pregnant women were allocated to 1 of 4 nutritional intervention arms: 1) iron and folic acid (FeFol) tablets (FeFol group); 2) multiple micronutrient (MMN) tablets (MMN group); 3) protein energy (PE) as a lipid-based nutrient supplement (LNS; PE group); and 4) PE and MMN (PE+MMN group) as LNS. All arms included iron (60 mg/d) and folic acid (400 μg/d). The MMN and PE+MMN arms included 30 mg supplemental Zn/d. In a subgroup of ∼300 mother-infant pairs, we measured maternal iron status, mRNA levels of genes encoding for placental iron and zinc transport proteins, and cord blood iron levels. Results: Maternal plasma iron concentration in late pregnancy was 45% and 78% lower in the PE and PE+MMN groups compared to the FeFol and MMN groups, respectively (P < 0.001). The mRNA levels of the placental iron uptake protein transferrin receptor 1 were 30–49% higher in the PE and PE+MMN arms than in the FeFol arm (P < 0.031), and also higher in the PE+MMN arm (29%; P = 0.042) than in the MMN arm. Ferritin in infant cord blood was 18–22% lower in the LNS groups (P < 0.024). Zinc supplementation in the MMN arm was associated with higher maternal plasma zinc concentrations (10% increase; P < 0.001) than in other intervention arms. mRNA levels for intracellular zinc-uptake proteins, in this case zrt, irt-like protein (ZIP) 4 and ZIP8, were 96–205% lower in the PE+MMN arm than in the intervention arms without added zinc (P < 0.025). Furthermore, mRNA expression of ZIP1 was 85% lower in the PE+MMN group than in the PE group (P = 0.003). Conclusion: In conditions of low maternal iron and in the absence of supplemental zinc, the placenta upregulates the gene expression of iron and zinc uptake proteins, presumably in order to meet fetal demands in the face of low maternal supply. The ENID trial was registered at www.controlled-trials.com as ISRCTN49285450.
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Affiliation(s)
- Modou Lamin Jobarteh
- Medical Research Council Unit The Gambia, Banjul, The Gambia.,Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Harry J McArdle
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Grietje Holtrop
- Biomathematics and Statistics Scotland (BioSS), Aberdeen, United Kingdom; and
| | - Ebrima A Sise
- Medical Research Council Unit The Gambia, Banjul, The Gambia
| | | | - Sophie E Moore
- Medical Research Council Unit The Gambia, Banjul, The Gambia; .,Division of Women's Health, King's College London, London, United Kingdom
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Abbas W, Adam I, Rayis DA, Hassan NG, Lutfi MF. Higher Rate of Iron Deficiency in Obese Pregnant Sudanese Women. Open Access Maced J Med Sci 2017; 5:285-289. [PMID: 28698743 PMCID: PMC5503723 DOI: 10.3889/oamjms.2017.059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 02/10/2017] [Accepted: 03/06/2017] [Indexed: 11/21/2022] Open
Abstract
AIM: To assess the association between obesity and iron deficiency (ID). MATERIAL AND METHODS: Pregnant women were recruited from Saad Abualila Hospital, Khartoum, Sudan, during January–April 2015. Medical history (age, parity, gestational age) was gathered using questionnaire. Weight and height were measured, and body mass index (BMI) was calculated. Women were sub-grouped based on BMI into underweight (< 18.5 kg/m^2), normal weight (18.5–24.9 kg/m^2), overweight (25–29.9 kg/m^2) and obese (≥ 30 kg/m^2). Serum ferritin and red blood indices were measured in all studied women. RESULTS: Two (0.5%), 126 (29.8%), 224 (53.0%) and 71 (16.8%) out of the 423 women were underweight, normal weight, overweight and obese, respectively. Anemia (Hb <11 g/dl), ID (ferritin <15µg/l) and iron deficiency anemia (IDA) were prevalent in 57.7%, 21.3% and 12.1%, respectively. Compared with the women with normal BMI, significantly fewer obese women were anemic [25 (35.2%) vs. 108 (85.7%), P < 0.001] and significantly higher number of obese women [25 (35.2) vs. 22 (17.5, P = 0.015] had iron deficiency. Linear regression analysis demonstrated a significant negative association between serum ferritin and BMI (– 0.010 µg/, P= 0.006). CONCLUSION: It is evident from the current findings that prevalence of anaemia and ID showed different trends about BMI of pregnant women
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Affiliation(s)
- Wisal Abbas
- Faculty of Medicine, Alneelain University, Khartoum, Sudan
| | - Ishag Adam
- Faculty of Medicine, University of Khartoum, P.O. Box 102, 11111, Khartoum, Sudan
| | - Duria A Rayis
- Faculty of Medicine, University of Khartoum, P.O. Box 102, 11111, Khartoum, Sudan
| | - Nada G Hassan
- Faculty of Medicine, University of Khartoum, P.O. Box 102, 11111, Khartoum, Sudan
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15
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Orlandini C, Torricelli M, Spirito N, Alaimo L, Di Tommaso M, Severi FM, Ragusa A, Petraglia F. Maternal anemia effects during pregnancy on male and female fetuses: are there any differences? J Matern Fetal Neonatal Med 2016; 30:1704-1708. [DOI: 10.1080/14767058.2016.1222607] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Cinzia Orlandini
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy,
| | - Michela Torricelli
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy,
| | - Nicoletta Spirito
- Department of Obstetric and Gynecology, Ospedale Apuane, Massa Carrara, Italy, and
| | - Lucia Alaimo
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy,
| | - Mariarosaria Di Tommaso
- Department of Health Sciences, Division of Pediatrics, Obstetrics and Gynecology and Nursing Science, University of Florence, Florence, Italy
| | | | - Antonio Ragusa
- Department of Obstetric and Gynecology, Ospedale Apuane, Massa Carrara, Italy, and
| | - Felice Petraglia
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy,
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16
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Abstract
Iron is an essential element for human development. It is a major requirement for cellular processes such as oxygen transport, energy metabolism, neurotransmitter synthesis, and myelin synthesis. Despite its crucial role in these processes, iron in the ferric form can also produce toxic reactive oxygen species. The duality of iron’s function highlights the importance of maintaining a strict balance of iron levels in the body. As a result, organisms have developed elegant mechanisms of iron uptake, transport, and storage. This review will focus on the mechanisms that have evolved at physiological barriers, such as the intestine, the placenta, and the blood–brain barrier (BBB), where iron must be transported. Much has been written about the processes for iron transport across the intestine and the placenta, but less is known about iron transport mechanisms at the BBB. In this review, we compare the established pathways at the intestine and the placenta as well as describe what is currently known about iron transport at the BBB and how brain iron uptake correlates with processes at these other physiological barriers.
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Affiliation(s)
- Kari A Duck
- Department of Neurosurgery, The Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - James R Connor
- Department of Neurosurgery, The Pennsylvania State University College of Medicine, Hershey, PA, USA.
- Department of Neurosurgery, Neural and Behavioral Sciences and Pediatrics, Center for Aging and Neurodegenerative Diseases, Penn State Hershey Medical Center, 500 University Drive, MC H110, C3830, Hershey, PA, 17033, USA.
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17
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Hu X, Wang R, Shan Z, Dong Y, Zheng H, Jesse FF, Rao E, Takahashi E, Li W, Teng W, Teng X. Perinatal Iron Deficiency-Induced Hypothyroxinemia Impairs Early Brain Development Regardless of Normal Iron Levels in the Neonatal Brain. Thyroid 2016; 26:891-900. [PMID: 27231981 DOI: 10.1089/thy.2015.0293] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Both perinatal hypothyroxinemia and perinatal iron deficiency (ID) are associated with poor neurodevelopment in offspring. Iron is an important component of thyroid peroxidase, a key enzyme in the synthesis of thyroid hormone. The authors' previous study demonstrated that perinatal ID can lead to maternal hypothyroxinemia during pregnancy. The goal of this study was to determine whether perinatal ID-associated hypothyroxinemia can cause brain defects prior to neonatal brain iron depletion. METHODS Two rat models were established to imitate the two common types of maternal ID (mild ID with anemia [ID + A] and ID without anemia [ID - A]), and iron limitation was initiated two weeks before pregnancy. Maternal and neonatal thyroid hormones in serum were analyzed at postnatal day (P) 0 and P10. Neonatal thyroid hormone, as well as mRNA expression of some thyroid hormone-responsive genes in the cerebral cortex and hippocampus, were measured at P10. Serum iron and brain iron concentrations were analyzed by inductively coupled plasma mass spectrometry. Liver iron concentration was determined using graphite furnace atomic absorption spectroscopy. Hemoglobin was analyzed with an automated blood coagulation analyzer. Surface righting reflex and vibrissae-evoked forelimb placing were measured to assess the sensorimotor behaviors. RESULTS It was found that pre-pregnant mild ID resulted in maternal hypothyroxinemia, which lasted from gestation day 13 to P10. Pre-pregnant mild ID decreased the neonatal brain total triiodothyronine level at P10. Consistent with a low total triiodothyronine level, the mRNA expression of some thyroid hormone-responsive genes (Mbp, RC3, and Srg1) were significantly reduced in the neonatal cerebral cortex and hippocampus in both ID rat models at P10. Furthermore, ID rat pups at P10 showed retarded sensorimotor skills. No significant difference was found between the control and the ID pups in terms of iron concentrations in the neonatal brain at P10. CONCLUSIONS This study demonstrates that perinatal ID-associated hypothyroxinemia is sufficient to impair early brain development, regardless of whether the neonatal brain iron level is normal, and monitoring thyroid hormone level is indicated in ID pregnant women.
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Affiliation(s)
- Xiaona Hu
- 1 Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University , Shenyang, China
- 2 Department of Endocrinology, The People's Hospital of Liaoning Province , Shenyang, China
| | - Ranran Wang
- 1 Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University , Shenyang, China
| | - Zhongyan Shan
- 1 Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University , Shenyang, China
| | - Yujie Dong
- 3 Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University , Shanghai, China
| | - Hongzhi Zheng
- 1 Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University , Shenyang, China
| | - Forrest Fabian Jesse
- 3 Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University , Shanghai, China
| | - Elizabeth Rao
- 3 Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University , Shanghai, China
| | - Eiki Takahashi
- 4 RIKEN Brain Science Institute , Research Resources Center, Support Unit for Animal Resources Development, Wako, Japan
| | - Weidong Li
- 3 Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University , Shanghai, China
| | - Weiping Teng
- 1 Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University , Shenyang, China
| | - Xiaochun Teng
- 1 Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University , Shenyang, China
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18
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Abstract
Optimal iron nutrition in utero is essential for development of the fetus and helps establish birth iron stores adequate to sustain growth in early infancy. In species with hemochorial placentas, such as humans and rodents, iron in the maternal circulation is transferred to the fetus by directly contacting placental syncytiotrophoblasts. Early kinetic studies provided valuable data on the initial uptake of maternal transferrin, an iron-binding protein, by the placenta. However, the remaining steps of iron trafficking across syncytiotrophoblasts and through the fetal endothelium into the fetal blood remain poorly characterized. Over the last 20 years, identification of transmembrane iron transporters and the iron regulatory hormone hepcidin has greatly expanded the knowledge of cellular iron transport and its regulation by systemic iron status. In addition, emerging human and animal data demonstrating comprised fetal iron stores in severe maternal iron deficiency challenge the classic dogma of exclusive fetal control over the transfer process and indicate that maternal and local signals may play a role in regulating this process. This review compiles current data on the kinetic, molecular, and regulatory aspects of placental iron transport and considers new questions and knowledge gaps raised by these advances.
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Affiliation(s)
- Chang Cao
- C. Cao and M.D. Fleming are with the Department of Pathology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Mark D Fleming
- C. Cao and M.D. Fleming are with the Department of Pathology, Boston Children's Hospital, Boston, Massachusetts, USA.
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19
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Garcia-Valdes L, Campoy C, Hayes H, Florido J, Rusanova I, Miranda MT, McArdle HJ. The impact of maternal obesity on iron status, placental transferrin receptor expression and hepcidin expression in human pregnancy. Int J Obes (Lond) 2015; 39:571-8. [PMID: 25614087 DOI: 10.1038/ijo.2015.3] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 11/08/2014] [Accepted: 12/16/2014] [Indexed: 01/07/2023]
Abstract
BACKGROUND Obesity is associated with decreased iron status, possibly due to a rise in hepcidin, an inflammatory protein known to reduce iron absorption. In animals, we have shown that maternal iron deficiency is minimised in the foetus by increased expression of placental transferrin receptor (pTFR1), resulting in increased iron transfer at the expense of maternal iron stores. OBJECTIVE This study examines the effect of obesity during pregnancy on maternal and neonatal iron status in human cohorts and whether the placenta can compensate for decreased maternal iron stores by increasing pTFR1 expression. SUBJECTS/METHODS A total of 240 women were included in this study. One hundred and fifty-eight placentas (Normal: 90; Overweight: 37; Obese: 31) were collected at delivery. Maternal iron status was measured by determining serum transferrin receptor (sTFR) and ferritin levels at 24 and 34 weeks and at delivery. Hepcidin in maternal and cord blood was measured by ELISA and pTFR1 in placentas by western blotting and real-time RT-PCR. RESULTS Low iron stores were more common in obese women. Hepcidin levels (ng ml(-1)) at the end of the pregnancy were higher in obese than normal women (26.03±12.95 vs 18.00±10.77, P<0.05). Maternal hepcidin levels were correlated with maternal iron status (sTFR r=0.2 P=0.025), but not with neonatal values. mRNA and protein levels of pTFR1 were both inversely related to maternal iron status. For mRNA and all women, sTFR r=0.2 P=0.044. Ferritin mRNA levels correlated only in overweight women r=-0.5 P=0.039 with hepcidin (r=0.1 P=0.349), irrespective of maternal body mass index (BMI). CONCLUSIONS The data support the hypothesis that obese pregnant women have a greater risk of iron deficiency and that hepcidin may be a regulatory factor. Further, we show that the placenta responds to decreased maternal iron status by increasing pTFR1 expression.
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Affiliation(s)
- L Garcia-Valdes
- 1] The Rowett Institute of Nutrition and Health, University of Aberdeen, Bucksburn, Aberdeen, UK [2] Department of Paediatrics, School of Medicine, University of Granada, Granada, Spain
| | - C Campoy
- Department of Paediatrics, School of Medicine, University of Granada, Granada, Spain
| | - H Hayes
- The Rowett Institute of Nutrition and Health, University of Aberdeen, Bucksburn, Aberdeen, UK
| | - J Florido
- Department Obstetrics and Gynaecology, School of Medicine, University of Granada, Granada, Spain
| | - I Rusanova
- Department of Paediatrics, School of Medicine, University of Granada, Granada, Spain
| | - M T Miranda
- Department of Biostatistics, School of Medicine, University of Granada, Granada, Spain
| | - H J McArdle
- The Rowett Institute of Nutrition and Health, University of Aberdeen, Bucksburn, Aberdeen, UK
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20
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Penha-Gonçalves C, Gozzelino R, de Moraes LV. Iron overload in Plasmodium berghei-infected placenta as a pathogenesis mechanism of fetal death. Front Pharmacol 2014; 5:155. [PMID: 25071574 PMCID: PMC4077027 DOI: 10.3389/fphar.2014.00155] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 06/12/2014] [Indexed: 11/17/2022] Open
Abstract
Plasmodium infection during gestation may lead to severe clinical manifestations including abortion, stillbirth, intrauterine growth retardation, and low birth weight. Mechanisms underlying such poor pregnancy outcomes are still unclear. In the animal model of severe placental malaria (PM), in utero fetal death frequently occurs and mothers often succumb to infection before or immediately after delivery. Plasmodium berghei-infected erythrocytes (IEs) continuously accumulate in the placenta, where they are then phagocytosed by fetal-derived placental cells, namely trophoblasts. Inside the phagosomes, disruption of IEs leads to the release of non-hemoglobin bound heme, which is subsequently catabolized by heme oxygenase-1 into carbon monoxide, biliverdin, and labile iron. Fine-tuned regulatory mechanisms operate to maintain iron homeostasis, preventing the deleterious effect of iron-induced oxidative stress. Our preliminary results demonstrate that iron overload in trophoblasts of P. berghei-infected placenta is associated with fetal death. Placentas which supported normally developing embryos showed no iron accumulation within the trophoblasts. Placentas from dead fetuses showed massive iron accumulation, which was associated with parasitic burden. Here we present preliminary data suggesting that disruption of iron homeostasis in trophoblasts during the course of PM is a consequence of heme accumulation after intense IE engulfment. We propose that iron overload in placenta is a pathogenic component of PM, contributing to fetal death. The mechanism through which it operates still needs to be elucidated.
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21
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Cao C, Pressman EK, Cooper EM, Guillet R, Westerman M, O'Brien KO. Placental heme receptor LRP1 correlates with the heme exporter FLVCR1 and neonatal iron status. Reproduction 2014; 148:295-302. [PMID: 24947444 DOI: 10.1530/rep-14-0053] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
LDL receptor-related protein 1 (LRP1) is a transmembrane receptor highly expressed in human placenta. It was recently found to be the receptor for heme and its plasma-binding protein hemopexin (Hx) and is integral to systemic heme clearance. Little is known about systemic concentrations of Hx during pregnancy and whether maternal Hx and placental LRP1 contributes to fetal iron (Fe) homeostasis during pregnancy. We hypothesized that placental LRP1 would be upregulated in maternal/neonatal Fe insufficiency and would be related to maternal circulating Hx. Placental LRP1 expression was assessed in 57 pregnant adolescents (14-18 years) in relationship with maternal and cord blood Fe status indicators (hemoglobin (Hb), serum ferritin, transferrin receptor), the Fe regulatory hormone hepcidin and serum Hx. Hx at mid-gestation correlated positively with Hb at mid-gestation (r=0.35, P=0.02) and Hx at delivery correlated positively with cord hepcidin (r=0.37, P=0.005). Placental LRP1 protein expression was significantly higher in women who exhibited greater decreases in serum Hx from mid-gestation to term (r=0.28, P=0.04). Significant associations were also found between placental LRP1 protein with cord hepcidin (r=-0.29, P=0.03) and placental heme exporter feline leukemia virus C receptor 1 (r=0.34, P=0.03). Our data are consistent with a role for placental heme Fe utilization in supporting fetal Fe demands.
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Affiliation(s)
- Chang Cao
- Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA
| | - Eva K Pressman
- Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA
| | - Elizabeth M Cooper
- Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA
| | - Ronnie Guillet
- Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA
| | - Mark Westerman
- Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA
| | - Kimberly O O'Brien
- Division of Nutritional SciencesCornell University, 230 Savage Hall, Ithaca, New York 14853, USASchool of MedicineUniversity of Rochester, Rochester, New York, USAIntrinsic LifeSciencesLa Jolla, California, USA
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Finkelstein JL, O'Brien KO, Abrams SA, Zavaleta N. Infant iron status affects iron absorption in Peruvian breastfed infants at 2 and 5 mo of age. Am J Clin Nutr 2013; 98:1475-84. [PMID: 24088721 DOI: 10.3945/ajcn.112.056945] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Effects of prenatal iron supplementation on maternal postpartum iron status and early infant iron homeostasis remain largely unknown. OBJECTIVE We examined iron absorption and growth in exclusively breastfed infants in relation to fetal iron exposure and iron status during early infancy. DESIGN Longitudinal, paired iron-absorption (⁵⁸Fe) studies were conducted in 59 exclusively breastfed Peruvian infants at 2-3 mo of age (2M) and 5-6 mo of age (5M). Infants were born to women who received ≥ 5100 or ≤ 1320 mg supplemental prenatal Fe. Iron status was assessed in mothers and infants at 2M and 5M. RESULTS Infant iron absorption from breast milk averaged 7.1% and 13.9% at 2M and 5M. Maternal iron status (at 2M) predicted infant iron deficiency (ID) at 5M. Although no infants were iron deficient at 2M, 28.6% of infants had depleted iron stores (ferritin concentration <12 μg/L) by 5M. Infant serum ferritin decreased (P < 0.0001), serum transferrin receptor (sTfR) increased (P < 0.0001), and serum iron decreased from 2M to 5M (P < 0.01). Higher infant sTfR (P < 0.01) and breast-milk copper (P < 0.01) predicted increased iron absorption at 5M. Prenatal iron supplementation had no effects on infant iron status or breast-milk nutrient concentrations at 2M or 5M. However, fetal iron exposure predicted increased infant length at 2M (P < 0.01) and 5M (P < 0.05). CONCLUSIONS Fetal iron exposure affected early infant growth but did not significantly improve iron status or absorption. Young, exclusively breastfed infants upregulated iron absorption when iron stores were depleted at both 2M and 5M.
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Affiliation(s)
- Julia L Finkelstein
- Division of Nutritional Sciences, Cornell University, Ithaca, NY (JLF and KOO); the USDA/Agricultural Research Service Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX (SAA); and the Instituto de Investigación Nutricional, Lima, Peru (NZ)
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23
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Abstract
BACKGROUND Fetal growth restriction is reported to be associated with impaired placental iron transport. Transferrin receptor (TfR) is a major placental iron transporter in humans but has not been studied in sheep. TfR is regulated by both iron and nitric oxide (NO), the molecule produced by endothelial nitric oxide synthase (eNOS). We hypothesized that limited placental development downregulates both placental TfR and eNOS expression, thereby lowering fetal tissue iron. METHODS An ovine surgical uterine space restriction (USR) model, combined with multifetal gestation, tested the extremes of uterine and placental adaptation. Blood, tissues, and placentomes from non-space restricted (NSR) singletons were compared with USR fetuses at gestational day (GD) 120 or 130. RESULTS When expressed proportionate to fetal weight, liver iron content did not differ, whereas renal iron was higher in USR vs. NSR fetuses. Renal TfR protein expression did not differ, but placental TfR expression was lower in USR fetuses at GD130. Placental levels of TfR correlated to eNOS. TfR was localized throughout the placentome, including the hemophagous zone, implicating a role for TfR in ovine placental iron transport. CONCLUSION Fetal iron was regulated in an organ-specific manner. In USR fetuses, NO-mediated placental adaptations may prevent the normal upregulation of placental TfR at GD130.
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Abstract
It has been nearly 15 years since the first review on pregnancy and iron deficiency was published in Nutrition Reviews. Many unresolved issues raised in that seminal review have been addressed. New proteins involved in nonheme and heme iron transport have been identified in the enterocyte, and information on the roles of these proteins in the placenta is evolving. The systemic iron regulatory hormone, hepcidin, has since been identified as a key regulator of iron homeostasis. Additional data on the efficacy and consequences of prenatal iron supplementation are available. Emerging data on developmental changes in iron absorption across early infancy have further emphasized the need to ensure that the iron endowment of the neonate at birth is optimal. This is especially important, given growing evidence linking neonatal iron status with subsequent cognitive and neurobehavioral outcomes. Along with the many advances, new questions and gaps in knowledge have been identified. This review summarizes new data on maternal iron utilization across pregnancy as it impacts the pregnant woman and the iron status of the neonate at birth.
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Affiliation(s)
- Chang Cao
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA
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25
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Sandovici I, Hoelle K, Angiolini E, Constância M. Placental adaptations to the maternal-fetal environment: implications for fetal growth and developmental programming. Reprod Biomed Online 2012; 25:68-89. [PMID: 22560117 DOI: 10.1016/j.rbmo.2012.03.017] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 03/06/2012] [Accepted: 03/08/2012] [Indexed: 12/16/2022]
Abstract
The placenta is a transient organ found in eutherian mammals that evolved primarily to provide nutrients for the developing fetus. The placenta exchanges a wide array of nutrients, endocrine signals, cytokines and growth factors with the mother and the fetus, thereby regulating intrauterine development. Recent studies show that the placenta is not just a passive organ mediating maternal-fetal exchange. It can adapt its capacity to supply nutrients in response to intrinsic and extrinsic variations in the maternal-fetal environment. These dynamic adaptations are thought to occur to maximize fetal growth and viability at birth in the prevailing conditions in utero. However, some of these adaptations may also affect the development of individual fetal tissues, with patho-physiological consequences long after birth. Here, this review summarizes current knowledge on the causes, possible mechanisms and consequences of placental adaptive responses, with a focus on the regulation of transporter-mediated processes for nutrients. This review also highlights the emerging roles that imprinted genes and epigenetic mechanisms of gene regulation may play in placental adaptations to the maternal-fetal environment.
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Affiliation(s)
- Ionel Sandovici
- Metabolic Research Laboratories, Department of Obstetrics and Gynaecology, University of Cambridge, United Kingdom.
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Tian Y, Zhao J, Zhao B, Gao Q, Xu J, Liu D. The ratio of sTfR/ferritin is associated with the expression level of TfR in rat bone marrow cells after endurance exercise. Biol Trace Elem Res 2012; 147:261-6. [PMID: 22207220 DOI: 10.1007/s12011-011-9312-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 12/19/2011] [Indexed: 10/14/2022]
Abstract
Currently, it is unclear which index of haematological parameters could be used to most easily monitor iron deficiency during endurance training. To address this question, 16 male Wistar rats were randomly assigned to two groups: a sedentary group (n = 8) and an exercised group (n = 8). Initially, animals in the exercise group started running on a treadmill at a rate of 30 m/min, on a 0% grade, for 1 min/session. Running time was gradually increased by 2 min/day. The training plan was one session per day during the initial 2 weeks and two sessions per day during the third to ninth week. At the end of the 9-week experiment, we analysed the blood of the experimental animals for haemoglobin levels, erythrocyte numbers, haematocrit, serum iron levels, total iron binding capacity, transferrin saturation, serum ferritin levels and soluble transferrin receptor (sTfR) levels, and we calculated the ratio of sTfR/ferritin. Erythrocyte numbers, haemoglobin levels and haematocrit values were decreased after 9 weeks of exercise, but sTfR and sTfR/ferritin values were increased (P < 0.01 or P < 0.05). The training regime significantly increased TfR mRNA levels in the bone marrow cells of the exercised rats compared with the sedentary group (1.8 ± 0.5 vs. 1.1 ± 0.2, P < 0.01). These results revealed a significant correlation between TfR levels in the bone marrow cells and the ratio of sTfR/ferritin (r = 0.517; P < 0.01) and sTfR levels (r = 0.206; P < 0.05) in sedentary and exercised rats. In conclusion, we show that sTfR indices and the ratio of sTfR/ferritin could be useful indicators for monitoring iron deficiency during endurance training.
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Affiliation(s)
- Ye Tian
- Sport Biological Center, China Institute of Sport Science, General Administration of Sport, No.11 Tiyuguan Road, Dongcheng District, Beijing, China, 100061
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Li YQ, Bai B, Cao XX, Yan H, Zhuang GH. Ferroportin 1 and hephaestin expression in BeWo cell line with different iron treatment. Cell Biochem Funct 2011; 30:249-55. [PMID: 22170436 DOI: 10.1002/cbf.1843] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 11/13/2011] [Accepted: 11/16/2011] [Indexed: 12/20/2022]
Abstract
The process of placental iron transfer is an important physiological process during pregnancy. However, the molecular mechanism of placental iron transport has not been completely elucidated until now. Ferroportin 1 (FPN1) and hephaestin (Heph) have been identified as the important molecules involved in duodenal iron export. However, whether they participate in the placental iron efflux has been undefined until now. In this study, the BeWo cells were treated with desferrioxamine and Holo-transferrin human in different concentrations and harvested at 48 and 72 h. The mRNA expression of FPN1 and Heph was detected with quantitative real-time polymerase chain reaction, and the protein expression was detected with western blots. The results showed an up-regulated FPN1 expression with desferrioxamine treatment and down-regulated expression with Holo-transferrin human supplementation. However, the change of FPN1 expression at protein level was limited. Heph expression enhanced when cells were treated with desferrioxamine although the quantity of Heph expression was low. Heph expression showed no significant change with Holo-transferrin human supplementation. It indicates that FPN1 may participate in placental iron transport, and placental FPN1 expression is obviously not dependent on the iron regular element/iron regular protein regulation. An alternatively spliced FPN1 isoform that lacks an iron regular element may be the predominant expression in BeWo cells. It also demonstrates that Heph is active in placenta but may not play a key role in placental iron transport because it is not the main part of placental copper oxidase.
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Affiliation(s)
- Yan-Qin Li
- Department of Public Health, Xi'an Jiaotong University College of Medicine, Xi'an, Shaanxi, China.
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Shpyleva SI, Tryndyak VP, Kovalchuk O, Starlard-Davenport A, Chekhun VF, Beland FA, Pogribny IP. Role of ferritin alterations in human breast cancer cells. Breast Cancer Res Treat 2011; 126:63-71. [PMID: 20390345 DOI: 10.1007/s10549-010-0849-4] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Accepted: 03/13/2010] [Indexed: 12/23/2022]
Abstract
Breast cancer is the most common malignancy in women. Successful treatment of breast cancer relies on a better understanding of the molecular mechanisms involved in breast cancer initiation and progression. Recent studies have suggested a crucial role of perturbations in ferritin levels and tightly associated with this, the deregulation of intracellular iron homeostasis; however, the underlying molecular mechanisms for the cancer-linked ferritin alterations remain largely unknown and often with conflicting conclusions. Therefore, this study was undertaken to define the role of ferritin in breast cancer. We determined that human breast cancer cells with an epithelial phenotype, such as MCF-7, MDA-MB-361, T-47D, HCC70 and cells, expressed low levels of ferritin light chain, ferritin heavy chain, transferrin, transferring receptor, and iron-regulatory proteins 1 and 2. In contrast, expression of these proteins was substantially elevated in breast cancer cells with an aggressive mesenchymal phenotype, such as Hs-578T, BT-549, and especially MDA-MB-231 cells. The up-regulation of ferritin light chain and ferritin heavy chain in MDA-MB-231 cells was accompanied by alterations in the subcellular distribution of these proteins as characterized by an increased level of nuclear ferritin and a lower level of the cellular labile iron pool as compared to MCF-7 cells. We established that ferritin heavy chain is a target of miRNA miR-200b, suggesting that its up-regulation in MDA-MB-231 cells may be triggered by the low expression of miR-200b. Ectopic up-regulation of miR-200b by transfection of MDA-MB-231 cells with miR-200b substantially decreased the level of ferritin heavy chain. More importantly, miR-200b-induced down-regulation of ferritin was associated with an increased sensitivity of the MDA-MB-231 cells to the chemotherapeutic agent doxorubicin. These results suggest that perturbations in ferritin levels are associated with the progression of breast cancer toward a more advanced malignant phenotype.
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Affiliation(s)
- Svitlana I Shpyleva
- Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, AR 72079, USA
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Impact of maternal and neonatal iron status on placental transferrin receptor expression in pregnant adolescents. Placenta 2010; 31:1010-4. [DOI: 10.1016/j.placenta.2010.08.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 08/13/2010] [Accepted: 08/17/2010] [Indexed: 02/05/2023]
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Transferrin receptor gene and protein expression and localization in human IUGR and normal term placentas. Placenta 2010; 32:44-50. [PMID: 21036394 DOI: 10.1016/j.placenta.2010.10.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 10/11/2010] [Accepted: 10/11/2010] [Indexed: 11/22/2022]
Abstract
Iron (Fe) deficiency in pregnancy is associated to low birth weight and premature delivery while in adults it can result in increased blood pressure and cardiovascular disease. Cellular Fe uptake is mediated by the Transferrin Receptor 1 (TFRC), located in the trophoblast membranes. Here, we measured TFRC mRNA expression (Real Time PCR) and TFRC protein expression and localization (Western Blotting and immunohistochemistry) in IUGR compared to control placentas. A total of 50 IUGR and 56 control placentas were studied at the time of elective cesarean section. IUGR was defined by ultrasound in utero, and confirmed by birth weight <10th percentile. Three different severity groups were identified depending on the umbilical artery pulsatility index and fetal heart rate. TFRC mRNA expression was significantly lower in IUGR placentas compared to controls (p < 0.05), and this was confirmed for TFRC protein levels. In both experiments the most severe IUGR group presented lower expression compared to the other groups, and this was also related to umbilical venous oxygen levels. TFRC protein localization in the villous trophoblast did not differ in the groups, and was predominantly present in the syncytiotrophoblast. In conclusion, these are the first observations about TFRC expression in human IUGR placentas, demonstrating its significant decrease in IUGR vs controls. Thus, Fe transport could be limited in IUGR placentas. Further studies are needed to study components of the placental Fe transport system and to clarify the regulation mechanisms involved in TFRC expression, possibly altered in IUGR placentas.
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Abstract
Premature infants are a population prone to nutrient deficiencies. Because the early diet of these infants is entirely amenable to intervention, understanding the pathophysiology behind these deficiencies is important for both the neonatologists who care for them acutely and for pediatricians who are responsible for their care through childhood. This article reviews the normal accretion of nutrients in the fetus, discusses specific nutrient deficiencies that are exacerbated in the postnatal period, and identifies key areas for future research.
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Abstract
Accurate assessment of maternal micronutrient status is critical to the prevention of suboptimal micronutrient status and anaemia during pregnancy. Measurement of Fe, folate and vitamin B12 status is complicated by adaptive changes to maternal and placental physiology that markedly affect concentrations of circulating micronutrients and their functional biomarkers. Validation of new assessment methods by comparison with gold standards is often prevented by ethical considerations. Antenatal screening in the UK is predominantly concerned with the detection of anaemia, although estimation of maternal Fe stores by serum ferritin at the start of antenatal care may be a more effective preventive strategy. Functional assessment of maternal anaemia is highly problematic, so instead reference data are used for its definition. The effect of mild-to-moderate anaemia on pregnancy outcome is unclear because of the crude nature of its assessment and the influence of confounding factors. Fe-deficient erythropoiesis may be detected by assessment of erythrocyte Zn protoporphyrin and reticulocyte Hb, although such measures may be unavailable in many clinical laboratories. Serum soluble transferrin receptor is highly responsive to tissue Fe deficiency and is less affected by inflammation than most other indicators. Direct inter-assay comparison of serum and erythrocyte folate values is inadvisable since recovery rates differ greatly between methods. Serum total homocysteine is a useful functional biomarker of both folate and vitamin B12 status but during pregnancy is influenced by other factors that reduce its sensitivity. Isotope-dilution liquid chromatography-tandem MS and serum holo-transcobalamin provide new opportunities to gain detailed data of folate species and vitamin B12 fractions in large samples.
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