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Stoffel NU, Drakesmith H. Effects of Iron Status on Adaptive Immunity and Vaccine Efficacy: A Review. Adv Nutr 2024; 15:100238. [PMID: 38729263 DOI: 10.1016/j.advnut.2024.100238] [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: 01/24/2024] [Revised: 05/02/2024] [Accepted: 05/06/2024] [Indexed: 05/12/2024] Open
Abstract
Vaccines can prevent infectious diseases, but their efficacy varies, and factors impacting vaccine effectiveness remain unclear. Iron deficiency is the most common nutrient deficiency, affecting >2 billion individuals. It is particularly common in areas with high infectious disease burden and in groups that are routinely vaccinated, such as infants, pregnant women, and the elderly. Recent evidence suggests that iron deficiency and low serum iron (hypoferremia) not only cause anemia but also may impair adaptive immunity and vaccine efficacy. A report of human immunodeficiency caused by defective iron transport underscored the necessity of iron for adaptive immune responses and spurred research in this area. Sufficient iron is essential for optimal production of plasmablasts and IgG responses by human B-cells in vitro and in vivo. The increased metabolism of activated lymphocytes depends on the high-iron acquisition, and hypoferremia, especially when occurring during lymphocyte expansion, adversely affects multiple facets of adaptive immunity, and may lead to prolonged inhibition of T-cell memory. In mice, hypoferremia suppresses the adaptive immune response to influenza infection, resulting in more severe pulmonary disease. In African infants, anemia and/or iron deficiency at the time of vaccination predict decreased response to diphtheria, pertussis, and pneumococcal vaccines, and response to measles vaccine may be increased by iron supplementation. In this review, we examine the emerging evidence that iron deficiency may limit adaptive immunity and vaccine responses. We discuss the molecular mechanisms and evidence from animal and human studies, highlight important unknowns, and propose a framework of key research questions to better understand iron-vaccine interactions.
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Affiliation(s)
- Nicole U Stoffel
- Medical Research Council Translational Immune Discovery Unit, Medical Research Council Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom.
| | - Hal Drakesmith
- Medical Research Council Translational Immune Discovery Unit, Medical Research Council Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
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Bah M, Verhoef H, Okoh E, Bah A, Prentice AM, Cerami C. Haem iron versus ferrous iron salts to treat iron deficiency anaemia in Gambian children: protocol for randomised controlled trial {1}. Trials 2024; 25:270. [PMID: 38641845 PMCID: PMC11027386 DOI: 10.1186/s13063-024-08101-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 04/10/2024] [Indexed: 04/21/2024] Open
Abstract
BACKGROUND The World Health Organization recommends universal iron supplementation for children aged 6-23 months in countries where anaemia is seen in over 40% of the population. Conventional ferrous salts have low efficacy due to low oral absorption in children with inflammation. Haem iron is more bioavailable, and its absorption may not be decreased by inflammation. This study aims to compare daily supplementation with haem iron versus ferrous sulphate on haemoglobin concentration and serum ferritin concentration after 12 weeks of supplementation. METHODS This will be a two-arm, randomised controlled trial. Gambian children aged 6-12 months with anaemia will be recruited within a predefined geographical area and recruited by trained field workers. Eligible participants will be individually randomised using a 1:1 ratio within permuted blocks to daily supplementation for 12 weeks with either 10.0 mg of elemental iron as haem or ferrous sulphate. Safety outcomes such as diarrhoea and infection-related adverse events will be assessed daily by the clinical team (see Bah et al. Additional file 4_Adverse event eCRF). Linear regression will be used to analyse continuous outcomes, with log transformation to normalise residuals as needed. Binary outcomes will be analysed by binomial regression or logistic regression, Primary analysis will be by modified intention-to-treat (i.e., those randomised and who ingested at least one supplement dose of iron), with multiple imputations to replace missing data. Effect estimates will be adjusted for baseline covariates (C-reactive protein, alpha-1-acid glycoprotein, haemoglobin, ferritin, soluble transferrin receptor). DISCUSSION This study will determine if therapeutic supplementation with haem iron is more efficacious than with conventional ferrous sulphate in enhancing haemoglobin and ferritin concentrations in anaemic children aged 6-12 months. TRIAL REGISTRATION Pan African Clinical Trial Registry PACTR202210523178727.
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Affiliation(s)
- Mamadou Bah
- Medical Research Council (MRC) Unit The Gambia at London School of Hygiene & Tropical Medicine (LSHTM), PO Box 273, Fajara, Banjul, The Gambia
- Division of Human Nutrition and Health, Wageningen University, PO Box 17, 6700, AA, Wageningen, The Netherlands
| | - Hans Verhoef
- Division of Human Nutrition and Health, Wageningen University, PO Box 17, 6700, AA, Wageningen, The Netherlands
| | - Emmanuel Okoh
- Medical Research Council (MRC) Unit The Gambia at London School of Hygiene & Tropical Medicine (LSHTM), PO Box 273, Fajara, Banjul, The Gambia
| | - Abdoulie Bah
- Medical Research Council (MRC) Unit The Gambia at London School of Hygiene & Tropical Medicine (LSHTM), PO Box 273, Fajara, Banjul, The Gambia
| | - Andrew M Prentice
- Medical Research Council (MRC) Unit The Gambia at London School of Hygiene & Tropical Medicine (LSHTM), PO Box 273, Fajara, Banjul, The Gambia
| | - Carla Cerami
- Medical Research Council (MRC) Unit The Gambia at London School of Hygiene & Tropical Medicine (LSHTM), PO Box 273, Fajara, Banjul, The Gambia.
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Silva NM, Lopes MDP, Schincaglia RM, Coelho ASG, Cominetti C, Hadler MCCM. Anaemia and iron deficiency associate with polymorphism TMPRSS6 rs855791 in Brazilian children attending day care centres. Br J Nutr 2024; 131:193-201. [PMID: 37605822 DOI: 10.1017/s0007114523001848] [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] [Indexed: 08/23/2023]
Abstract
Fe-deficiency anaemia is a major public health concern in children under 5 years of age. TMPRSS6 gene, encoding matriptase-2 protein, is implicated in Fe homoeostasis and has been associated with anaemia and Fe status in various populations. The aim of this cross-sectional study was to investigate the associations between the single nucleotide polymorphism (SNP) TMPRSS6 rs855791 and biomarkers of anaemia and Fe deficiency in Brazilian children attending day care centres. A total of 163 children aged 6-42 months were evaluated. Socio-economic, demographic, biochemical, haematological, immunological and genotype data were collected. Multiple logistic and linear regressions with hierarchical selection were used to assess the effects of independent variables on categorised outcomes and blood marker concentrations. Minor allele (T) frequency of rs855791 was 0·399. Each copy of the T allele was associated with a 4·49-fold increased risk of developing anaemia (P = 0·005) and a 4·23-fold increased risk of Fe deficiency assessed by serum soluble transferrin receptor (sTfR) (P < 0·001). The dose of the T allele was associated with an increase of 0·18 mg/l in sTfR concentrations and reductions of 1·41 fl and 0·52 pg in mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH), respectively. In conclusion, the T allele of SNP TMPRSS6 rs855791 was significantly associated with anaemia and Fe deficiency assessed by sTfR in Brazilian children attending day care centres. The effect was dose dependent, with each copy of the T allele being associated with lower MCV and MCH and higher concentrations of sTfR.
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Affiliation(s)
- Natalia Menezes Silva
- Graduate Program in Health Sciences, School of Medicine, Federal University of Goiás, Goiânia, GO, Brazil
| | - Mirella de Paiva Lopes
- Graduate Program in Nutrition and Health, School of Nutrition, Federal University of Goiás, Goiânia, GO74605-080, Brazil
| | | | | | - Cristiane Cominetti
- Nutritional Genomics Research Group, Nutrition and Health Graduation Program, School of Nutrition, Federal University of Goiás, Goiânia, GO, Brazil
| | - Maria Claret Costa Monteiro Hadler
- Graduate Program in Health Sciences, School of Medicine, Federal University of Goiás, Goiânia, GO, Brazil
- Graduate Program in Nutrition and Health, School of Nutrition, Federal University of Goiás, Goiânia, GO74605-080, Brazil
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Brittenham GM, Moir-Meyer G, Abuga KM, Datta-Mitra A, Cerami C, Green R, Pasricha SR, Atkinson SH. Biology of Anemia: A Public Health Perspective. J Nutr 2023; 153 Suppl 1:S7-S28. [PMID: 37778889 DOI: 10.1016/j.tjnut.2023.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 05/04/2023] [Accepted: 07/31/2023] [Indexed: 10/03/2023] Open
Abstract
Our goal is to present recent progress in understanding the biological mechanisms underlying anemia from a public health perspective. We describe important advances in understanding common causes of anemia and their interactions, including iron deficiency (ID), lack of other micronutrients, infection, inflammation, and genetic conditions. ID develops if the iron circulating in the blood cannot provide the amounts required for red blood cell production and tissue needs. ID anemia develops as iron-limited red blood cell production fails to maintain the hemoglobin concentration above the threshold used to define anemia. Globally, absolute ID (absent or reduced body iron stores that do not meet the need for iron of an individual but may respond to iron supplementation) contributes to only a limited proportion of anemia. Functional ID (adequate or increased iron stores that cannot meet the need for iron because of the effects of infection or inflammation and does not respond to iron supplementation) is frequently responsible for anemia in low- and middle-income countries. Absolute and functional ID may coexist. We highlight continued improvement in understanding the roles of infections and inflammation in causing a large proportion of anemia. Deficiencies of nutrients other than iron are less common but important in some settings. The importance of genetic conditions as causes of anemia depends upon the specific inherited red blood cell abnormalities and their prevalence in the settings examined. From a public health perspective, each setting has a distinctive composition of components underlying the common causes of anemia. We emphasize the coincidence between regions with a high prevalence of anemia attributed to ID (both absolute and functional), those with endemic infections, and those with widespread genetic conditions affecting red blood cells, especially in sub-Saharan Africa and regions in Asia and Oceania.
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Affiliation(s)
- Gary M Brittenham
- Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, NY, United States.
| | - Gemma Moir-Meyer
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Kelvin Mokaya Abuga
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Ananya Datta-Mitra
- Department of Pathology and Laboratory Medicine, University of California, Davis, CA, United States
| | - Carla Cerami
- The Medical Research Council Unit, The Gambia, London School of Hygiene and Tropical Medicine, London, UK
| | - Ralph Green
- Department of Pathology and Laboratory Medicine, University of California, Davis, CA, United States
| | - Sant-Rayn Pasricha
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia; Diagnostic Haematology, The Royal Melbourne Hospital; and Clinical Haematology at the Peter MacCallum Cancer Centre and The Royal Melbourne Hospital, Parkville, VIC Australia
| | - Sarah H Atkinson
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya; Department of Paediatrics, University of Oxford, Oxford, UK
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McCann S, Mason L, Milosavljevic B, Mbye E, Touray E, Colley A, Johnson W, Lloyd-Fox S, Elwell CE, Moore SE. Iron status in early infancy is associated with trajectories of cognitive development up to pre-school age in rural Gambia. PLOS GLOBAL PUBLIC HEALTH 2023; 3:e0002531. [PMID: 37910494 PMCID: PMC10619872 DOI: 10.1371/journal.pgph.0002531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 10/03/2023] [Indexed: 11/03/2023]
Abstract
INTRODUCTION Iron deficiency is among the leading risk factors for poor cognitive development. However, interventions targeting iron deficiency have had mixed results on cognitive outcomes. This may be due to previous interventions focusing on the correction of iron deficiency anaemia in late infancy and early childhood, at which point long lasting neural impacts may already be established. We hypothesise that the relationship between iron status and cognitive development will be observable in the first months of life and will not be recovered by 5 years of age. METHODS Using data from the Brain Imaging for Global Health (BRIGHT) Study in Gambia (n = 179), we conducted mixed effects modelling to assess the relationship between iron status at 5 months of age and trajectories of cognitive development from 5 months- 5 years using (i) a standardised measure of cognitive development (Mullen Scales of Early Learning) and (ii) an eye-tracking assessment of attention processing (visual disengagement time). RESULTS All infants were iron sufficient at 1 month of age. At 5 and 12 months of age 30% and 55% of infants were iron deficient respectively. In fully adjusted analyses, infants in the lowest tercile of soluble transferrin receptor (sTfR) (best iron status) achieved MSEL Cognitive Scores on average 1.9 points higher than infants in the highest sTfR tercile (p = 0.009, effect size = 0.48). There was no evidence that this group difference was recovered by 5 years of age. Infants in the lowest sTfR tercile had visual disengagement time 57ms faster than the highest tercile (p = 0.001, effect size = 0.59). However, this difference diminished by early childhood (p = 0.024). CONCLUSION Infants are at risk of iron deficiency in early infancy. A relationship between iron status and cognitive development is apparent from 5 months of age and remains observable at 5 years of age. One mechanism by which iron availability in early infancy impacts brain development may be through effects on early attentional processing, which is rapidly developing and has substantial nutritional requirements during this period. To support neurocognitive development, prevention of iron deficiency in pre- and early postnatal life may be more effective than correcting iron deficiency once already established.
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Affiliation(s)
- Samantha McCann
- Department of Women and Children’s Health, King’s College London, London, United Kingdom
| | - Luke Mason
- Institute of Psychology, Psychiatry and Neuroscience, King’s College London, London, United Kingdom
| | | | - Ebrima Mbye
- Medical Research Council Unit, The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Ebou Touray
- Medical Research Council Unit, The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Alhassan Colley
- Medical Research Council Unit, The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - William Johnson
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| | - Sarah Lloyd-Fox
- Department of Psychology, University of Cambridge, Cambridge, United Kingdom
| | - Clare E. Elwell
- Department of Medical Physics, University College London, London, United Kingdom
| | - Sophie E. Moore
- Department of Women and Children’s Health, King’s College London, London, United Kingdom
- Medical Research Council Unit, The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
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Karthikappallil R, Atkinson SH. Universal iron supplementation: the best strategy to tackle childhood anaemia in malaria-endemic countries? Wellcome Open Res 2023; 8:345. [PMID: 37786779 PMCID: PMC10541535 DOI: 10.12688/wellcomeopenres.19750.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2023] [Indexed: 10/04/2023] Open
Abstract
Iron deficiency presents a major public health concern in many malaria-endemic regions, and both conditions affect young children most severely. Daily iron supplementation is the standard public health intervention recommended to alleviate rates of iron deficiency in children, but there is controversy over whether universal supplementation could increase the incidence and severity of malaria infection. Current evidence suggests that iron supplementation of deficient individuals is safe and effective in high-transmission settings when accompanied by malaria prevention strategies. However, low-resource settings often struggle to effectively control the spread of malaria, and it remains unclear whether supplementation of iron replete individuals could increase their risk of malaria and other infections. This review explores the evidence for and against universal iron supplementation programmes, and alternative strategies that could be used to alleviate iron deficiency in malaria-endemic areas, while minimising potential harm.
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Affiliation(s)
- Roshan Karthikappallil
- Department of Paediatrics, University of Oxford, Oxford, England, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, England, UK
| | - Sarah H. Atkinson
- Department of Paediatrics, University of Oxford, Oxford, England, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, England, UK
- Kenya Medical Research Institute (KEMRI) Centre for Geographic Medicine Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
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Sukhbaatar N, Schöller M, Fritsch SD, Linke M, Horer S, Träger M, Mazić M, Forisch S, Gonzales K, Kahler JP, Binder C, Lassnig C, Strobl B, Müller M, Scheiber-Mojdehkar B, Gundacker C, Dabsch S, Kain R, Hengstschläger M, Verhelst SHL, Weiss G, Theurl I, Weichhart T. Duodenal macrophages control dietary iron absorption via local degradation of transferrin. Blood 2023; 141:2878-2890. [PMID: 37018657 PMCID: PMC10646810 DOI: 10.1182/blood.2022016632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 02/15/2023] [Accepted: 02/15/2023] [Indexed: 04/07/2023] Open
Abstract
Iron is an essential cellular metal that is important for many physiological functions including erythropoiesis and host defense. It is absorbed from the diet in the duodenum and loaded onto transferrin (Tf), the main iron transport protein. Inefficient dietary iron uptake promotes many diseases, but mechanisms regulating iron absorption remain poorly understood. By assessing mice that harbor a macrophage-specific deletion of the tuberous sclerosis complex 2 (Tsc2), a negative regulator of mechanistic target of rapamycin complex 1 (mTORC1), we found that these mice possessed various defects in iron metabolism, including defective steady-state erythropoiesis and a reduced saturation of Tf with iron. This iron deficiency phenotype was associated with an iron import block from the duodenal epithelial cells into the circulation. Activation of mTORC1 in villous duodenal CD68+ macrophages induced serine protease expression and promoted local degradation of Tf, whereas the depletion of macrophages in mice increased Tf levels. Inhibition of mTORC1 with everolimus or serine protease activity with nafamostat restored Tf levels and Tf saturation in the Tsc2-deficient mice. Physiologically, Tf levels were regulated in the duodenum during the prandial process and Citrobacter rodentium infection. These data suggest that duodenal macrophages determine iron transfer to the circulation by controlling Tf availability in the lamina propria villi.
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Affiliation(s)
- Nyamdelger Sukhbaatar
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Maria Schöller
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | | | - Monika Linke
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Stefanie Horer
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Manuela Träger
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Mario Mazić
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Stephan Forisch
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Karine Gonzales
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Jan Pascal Kahler
- Laboratory of Chemical Biology, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Carina Binder
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Caroline Lassnig
- Biomodels Austria and Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Birgit Strobl
- Biomodels Austria and Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Mathias Müller
- Biomodels Austria and Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | | | - Claudia Gundacker
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Stefanie Dabsch
- Division of Gastroenterology and Hepatology, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Renate Kain
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Markus Hengstschläger
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Steven H. L. Verhelst
- Laboratory of Chemical Biology, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Günter Weiss
- Department of Internal Medicine II, Medical University of Innsbruck, Innsbruck, Austria
| | - Igor Theurl
- Department of Internal Medicine II, Medical University of Innsbruck, Innsbruck, Austria
| | - Thomas Weichhart
- Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
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Wegmüller R, Bah A, Kendall L, Goheen MM, Sanyang S, Danso E, Sise EA, Jallow A, Verhoef H, Jallow MW, Wathuo M, Armitage AE, Drakesmith H, Pasricha SR, Cross JH, Cerami C, Prentice AM. Hepcidin-guided screen-and-treat interventions for young children with iron-deficiency anaemia in The Gambia: an individually randomised, three-arm, double-blind, controlled, proof-of-concept, non-inferiority trial. Lancet Glob Health 2023; 11:e105-e116. [PMID: 36521942 PMCID: PMC9764454 DOI: 10.1016/s2214-109x(22)00449-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 09/22/2022] [Accepted: 10/04/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND Iron deficiency is the most prevalent nutritional disorder worldwide. Iron supplementation has modest efficacy, causes gastrointestinal side-effects that limit compliance, and has been associated with serious adverse outcomes in children across low-income settings. We aimed to compare two hepcidin-guided screen-and-treat regimens designed to reduce overall iron dosage by targeting its administration to periods when children were safe and ready to receive iron supplementation, with WHO's recommendation of universal iron supplementation. METHODS We conducted an individually randomised, three-arm, double-blind, controlled, proof-of-concept, non-inferiority trial in 12 rural communities across The Gambia. Eligible participants were children aged 6-23 months with anaemia. Participants were randomly assigned (1:1:1) to either the WHO recommended regimen of one sachet of multiple micronutrient powder (MMP) daily containing 12·0 mg iron as encapsulated ferrous fumarate (control group); to MMP with 12·0 mg per day iron for the next 7 days if plasma hepcidin concentration was less than 5·5 μg/L, or to MMP without iron for the next 7 days if plasma hepcidin concentration was at least 5·5 μg/L (12 mg screen-and-treat group); or to MMP with 6·0 mg per day iron for the next 7 days if plasma hepcidin concentration was less than 5·5 μg/L, or to MMP without iron for the next 7 days if plasma hepcidin concentration was at least 5·5 μg/L (6 mg screen-and-treat group). Randomisation was done by use of a permuted block design (block size of 9), with stratification by haemoglobin and age, using computer-generated numbers. Participants and the research team (except for the data manager) were masked to group allocation. The primary outcome was haemoglobin concentration, with a non-inferiority margin of -5 g/L. A per-protocol analysis, including only children who had consumed at least 90% of the supplements (ie, supplement intake on ≥75 days during the study), was done to assess non-inferiority of the primary outcome at day 84 using a one-sided t test adjusted for multiple comparisons. Safety was assessed by use of ex-vivo growth tests of Plasmodium falciparum in erythrocytes and three species of sentinel bacteria in plasma samples from participants. This trial is registered with the ISRCTN registry, ISRCTN07210906. FINDINGS Between April 23, 2014, and Aug 7, 2015, we prescreened 783 children, of whom 407 were enrolled into the study: 135 were randomly assigned to the control group, 136 to the 12 mg screen-and-treat group, and 136 to the 6 mg screen-and-treat group. 345 (85%) children were included in the per-protocol population: 115 in the control group, 116 in the 12 mg screen-and-treat group, and 114 in the 6 mg screen-and-treat group. Directly observed adherence was high across all groups (control group 94·8%, 12 mg screen-and-treat group 95·3%, and 6 mg screen-and-treat group 95·0%). 82 days of iron supplementation increased mean haemoglobin concentration by 7·7 g/L (95% CI 3·2 to 12·2) in the control group. Both screen-and-treat regimens were significantly less efficacious at improving haemoglobin (-5·6 g/L [98·3% CI -9·9 to -1·3] in the 12 mg screen-and-treat group and -7·8 g/L [98·3% CI -12·2 to -3·5] in the 6 mg screen-and-treat group) and neither regimen met the preset non-inferiority margin of -5 g/L. The 12 mg screen-and-treat regimen reduced iron dosage to 6·1 mg per day and the 6 mg screen-and-treat regimen reduced dosage to 3·0 mg per day. 580 adverse events were observed in 316 participants, of which eight were serious adverse events requiring hospitalisation mainly due to diarrhoeal disease (one [1%] participant in the control group, three [2%] in the 12 mg screen-and-treat group, and four [3%] in the 6 mg screen-and-treat group). The most common causes of non-serious adverse events (n=572) were diarrhoea (145 events [25%]), upper respiratory tract infections (194 [34%]), lower respiratory tract infections (62 [11%]), and skin infections (122 [21%]). No adverse events were deemed to be related to the study interventions. INTERPRETATION The hepcidin-guided screen-and-treat strategy to target iron administration succeeded in reducing overall iron dosage, but was considerably less efficacious at increasing haemoglobin and combating iron deficiency and anaemia than was WHO's standard of care, and showed no differences in morbidity or safety outcomes. FUNDING Bill & Melinda Gates Foundation and UK Medical Research Council.
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Affiliation(s)
- Rita Wegmüller
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia; GroundWork, Fläsch, Switzerland
| | - Amat Bah
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia; National Nutrition Agency, Bakau, The Gambia
| | - Lindsay Kendall
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Morgan M Goheen
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia; Department of Internal Medicine, Yale University, New Haven, CT, USA
| | - Saikou Sanyang
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Ebrima Danso
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Ebrima A Sise
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Amadou Jallow
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Hans Verhoef
- Wageningen University & Research, Wageningen, Netherlands
| | - Momodou W Jallow
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia; Regeneron Genetics Center, Tarrytown, NY, USA
| | - Miriam Wathuo
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia; One Acre Fund, Kigali, Rwanda
| | - Andrew E Armitage
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Hal Drakesmith
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Sant-Rayn Pasricha
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - James H Cross
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Carla Cerami
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia
| | - Andrew M Prentice
- Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia.
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Davis JN, Williams A, Arnold CD, Rohner F, Wirth JP, Addo Y, Flores-Ayala RC, Oaks BM, Young MF, Suchdev PS, Engle-Stone R. The Relationship Between Ferritin and BMI is Mediated by Inflammation Among Women in Higher-Income Countries, But Not in Most Lower-Income Countries Nor Among Young Children: A Multi-Country Analysis. Curr Dev Nutr 2022; 6:nzac139. [PMID: 36475018 PMCID: PMC9718651 DOI: 10.1093/cdn/nzac139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 08/26/2022] [Accepted: 08/30/2022] [Indexed: 10/03/2023] Open
Abstract
Background In the presence of inflammation, the serum or plasma ferritin concentration ("ferritin" hereafter) transiently increases, confounding its interpretation as an iron status marker. The extent to which adiposity-related inflammation may influence ferritin interpretation is uncertain. Objectives We describe relationships between weight status, inflammation, and ferritin among nonpregnant women of reproductive age (WRA; 15-49 years) and preschool-age children (PSC; 6-59 months) with normal weight to overweight or obesity (OWOB) in differing geographic settings. Methods Cross-sectional data were separately analyzed from 18 surveys (WRA) and 25 surveys (PSC) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project, excluding observations with underweight, wasting, pregnancy, or malaria. Relationships were assessed between BMI (in WRA) or BMI-for-age z-score (BAZ; in PSC), inflammatory biomarkers of C-reactive protein (CRP) and/or α-1-acid glycoprotein (AGP), ferritin by linear regression, and potential mediation by CRP and/or AGP in relationships between BMI or BAZ and ferritin with structural equation modeling. Regression and mediation models accounted for complex survey designs. Results were grouped by World Bank income classifications. Results In 5 of 6 surveys among WRA from upper-middle and high-income countries, ferritin was significantly positively associated with BMI, and this relationship was partially (or fully, in the United States) mediated by CRP and/or AGP. Mediation was present in 4 of 12 surveys for WRA in low- and lower-middle income countries. Among PSC, ferritin was positively associated with CRP and/or AGP in all surveys, but there were no significant CRP- or AGP-mediated relationships between ferritin and BAZ, except a negative relationship in the Philippines. Conclusions Where having OWOB is common among WRA, measurements of inflammatory biomarkers and their uses in interpreting ferritin may improve iron status assessments. While these relationships were inconsistent among PSC, inflammation was common and should be measured to interpret iron status. Included Kenyan trial data are registered at clinicaltrials.gov as NCT01088958.
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Affiliation(s)
- Jennie N Davis
- University of California, Davis Department of Nutrition, Institute for Global Nutrition, Davis, CA, USA
| | - Anne Williams
- University of Otago, Department of Human Nutrition, Dunedin, New Zealand
| | - Charles D Arnold
- University of California, Davis Department of Nutrition, Institute for Global Nutrition, Davis, CA, USA
| | | | | | - Yaw Addo
- Division of Nutrition, Physical Activity and Obesity, Centers for Disease Control and Prevention, Chamblee, GA, USA
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Rafael C Flores-Ayala
- Division of Nutrition, Physical Activity and Obesity, Centers for Disease Control and Prevention, Chamblee, GA, USA
| | - Brietta M Oaks
- Department of Nutrition and Food Sciences, University of Rhode Island, Kingston, RI, USA
| | - Melissa F Young
- Global Health Department, Emory University, Atlanta, GA, USA
| | - Parminder S Suchdev
- Department of Pediatrics and Global Health, Emory University, Atlanta, GA, USA
- Division of Global Health Protection, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Reina Engle-Stone
- University of California, Davis Department of Nutrition, Institute for Global Nutrition, Davis, CA, USA
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10
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Szklarz M, Gontarz-Nowak K, Matuszewski W, Bandurska-Stankiewicz E. Can Iron Play a Crucial Role in Maintaining Cardiovascular Health in the 21st Century? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:11990. [PMID: 36231287 PMCID: PMC9565681 DOI: 10.3390/ijerph191911990] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/01/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
In the 21st century the heart is facing more and more challenges so it should be brave and iron to meet these challenges. We are living in the era of the COVID-19 pandemic, population aging, prevalent obesity, diabetes and autoimmune diseases, environmental pollution, mass migrations and new potential pandemic threats. In our article we showed sophisticated and complex regulations of iron metabolism. We discussed the impact of iron metabolism on heart diseases, treatment of heart failure, diabetes and obesity. We faced the problems of constant stress, climate change, environmental pollution, migrations and epidemics and showed that iron is really essential for heart metabolism in the 21st century.
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11
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Lambrecht NJ, Bridges D, Wilson ML, Adu B, Eisenberg JNS, Folson G, Baylin A, Jones AD. Associations of bacterial enteropathogens with systemic inflammation, iron deficiency, and anemia in preschool-age children in southern Ghana. PLoS One 2022; 17:e0271099. [PMID: 35802561 PMCID: PMC9269377 DOI: 10.1371/journal.pone.0271099] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 06/23/2022] [Indexed: 11/19/2022] Open
Abstract
Anemia remains a pervasive public health problem among preschool-age children in Ghana. Recent analyses have found that anemia in Ghanaian children, particularly in Southern regions, is largely attributable to infectious causes, rather than nutritional factors. Infections with enteropathogens can reduce iron absorption and increase systemic inflammation, but few studies have examined direct links between enteropathogens and anemia. This study investigated associations between detection of individual bacterial enteropathogens and systemic inflammation, iron deficiency, and anemia among 6- to 59-month-old children in Greater Accra, Ghana. Serum samples were analyzed from a cross-sectional sample of 262 children for concentrations of hemoglobin (Hb), biomarkers of systemic inflammation [C-reactive protein (CRP) and α-1-acid glycoprotein (AGP)], and biomarkers of iron status [serum ferritin (SF) and serum transferrin receptor (sTfR)]. Stool samples were analyzed for ten bacterial enteropathogens using qPCR. We estimated associations between presence of each enteropathogen and elevated systemic inflammation (CRP > 5 mg/L and AGP > 1 g/L), iron deficiency (SF < 12 μg/L and sTfR > 8.3 mg/L) and anemia (Hb < 110 g/L). Enteropathogens were detected in 87% of children’s stool despite a low prevalence of diarrhea (6.5%). Almost half (46%) of children had anemia while one-quarter (24%) had iron deficiency (low SF). Despite finding no associations with illness symptoms, Campylobacter jejuni/coli detection was strongly associated with elevated CRP [Odds Ratio (95% CI): 3.49 (1.45, 8.41)] and elevated AGP [4.27 (1.85, 9.84)]. Of the pathogens examined, only enteroinvasive Escherichia coli/Shigella spp. (EIEC/Shigella) was associated with iron deficiency, and enteroaggregative Escherichia coli (EAEC) [1.69 (1.01, 2.84)] and EIEC/Shigella [2.34 (1.15, 4.76)] were associated with anemia. These results suggest that certain enteroinvasive pathogenic bacteria may contribute to child anemia. Reducing exposure to enteropathogens through improved water, sanitation, and hygiene practices may help reduce the burden of anemia in young Ghanaian children.
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Affiliation(s)
- Nathalie J. Lambrecht
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
- Institute of Public Health, Charité, Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Research Department 2, Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, Potsdam, Germany
- * E-mail:
| | - Dave Bridges
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Mark L. Wilson
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Bright Adu
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - Joseph N. S. Eisenberg
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Gloria Folson
- Department of Nutrition, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - Ana Baylin
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Andrew D. Jones
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan, United States of America
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12
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Roberts SA, Brabin L, Tinto H, Gies S, Diallo S, Brabin B. Seasonal patterns of malaria, genital infection, nutritional and iron status in non-pregnant and pregnant adolescents in Burkina Faso: a secondary analysis of trial data. BMC Public Health 2021; 21:1764. [PMID: 34579679 PMCID: PMC8477466 DOI: 10.1186/s12889-021-11819-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 09/16/2021] [Indexed: 11/21/2022] Open
Abstract
Background Adolescents are considered at high risk of developing iron deficiency. Studies in children indicate that the prevalence of iron deficiency increased with malaria transmission, suggesting malaria seasonally may drive iron deficiency. This paper examines monthly seasonal infection patterns of malaria, abnormal vaginal flora, chorioamnionitis, antibiotic and antimalarial prescriptions, in relation to changes in iron biomarkers and nutritional indices in adolescents living in a rural area of Burkina Faso, in order to assess the requirement for seasonal infection control and nutrition interventions. Methods Data collected between April 2011 and January 2014 were available for an observational seasonal analysis, comprising scheduled visits for 1949 non-pregnant adolescents (≤19 years), (315 of whom subsequently became pregnant), enrolled in a randomised trial of periconceptional iron supplementation. Data from trial arms were combined. Body Iron Stores (BIS) were calculated using an internal regression for ferritin to allow for inflammation. At recruitment 11% had low BIS (< 0 mg/kg). Continuous outcomes were fitted to a mixed-effects linear model with month, age and pregnancy status as fixed effect covariates and woman as a random effect. Dichotomous infection outcomes were fitted with analogous logistic regression models. Results Seasonal variation in malaria parasitaemia prevalence ranged between 18 and 70% in non-pregnant adolescents (P < 0.001), peaking at 81% in those who became pregnant. Seasonal variation occurred in antibiotic prescription rates (0.7–1.8 prescriptions/100 weekly visits, P < 0.001) and chorioamnionitis prevalence (range 15–68%, P = 0.026). Mucosal vaginal lactoferrin concentration was lower at the end of the wet season (range 2–22 μg/ml, P < 0.016), when chorioamnionitis was least frequent. BIS fluctuated annually by up to 53.2% per year around the mean BIS (5.1 mg/kg2, range 4.1–6.8 mg/kg), with low BIS (< 0 mg/kg) of 8.7% in the dry and 9.8% in the wet seasons (P = 0.36). Median serum transferrin receptor increased during the wet season (P < 0.001). Higher hepcidin concentration in the wet season corresponded with rising malaria prevalence and use of prescriptions, but with no change in BIS. Mean Body Mass Index and Mid-Upper-Arm-Circumference values peaked mid-dry season (both P < 0.001). Conclusions Our analysis supports preventive treatment of malaria among adolescents 15–19 years to decrease their disease burden, especially asymptomatic malaria. As BIS were adequate in most adolescents despite seasonal malaria, a requirement for programmatic iron supplementation was not substantiated. Supplementary Information The online version contains supplementary material available at 10.1186/s12889-021-11819-0.
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Affiliation(s)
- Stephen A Roberts
- Division of Population Health, Health Services Research and Primary Care, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre (MAHSC), Oxford Road, Manchester, M139PL, UK
| | - Loretta Brabin
- Division of Population Health, Health Services Research and Primary Care, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre (MAHSC), Oxford Road, Manchester, M139PL, UK.
| | - Halidou Tinto
- Clinical Research Unit of Nanoro, (IRSS-URCN), B.P.218, Ouagadougou, 11, Burkina Faso
| | - Sabine Gies
- Department of Biomedical Sciences, Prince Leopold Institute of Tropical Medicine, Antwerp, Belgium.,Medical Mission Institute, 97074, Würzburg, Germany
| | - Salou Diallo
- Clinical Research Unit of Nanoro, (IRSS-URCN), B.P.218, Ouagadougou, 11, Burkina Faso
| | - Bernard Brabin
- Liverpool School of Tropical Medicine and Institute of Infection and Global Health, University of Liverpool, Liverpool, L7 3EA, UK.,Global Child Health Group, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
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13
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Speich C, Brittenham GM, Cercamondi CI, Zeder C, Nkosi-Gondwe T, Phiri KS, Moretti D, Zimmermann MB. Isotopic measurement of iron requirements in sub-Saharan African children. Am J Clin Nutr 2021; 114:986-996. [PMID: 34113969 DOI: 10.1093/ajcn/nqab161] [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: 11/29/2020] [Accepted: 04/19/2021] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Prevention of iron deficiency in African children is a public health priority. Current WHO/FAO estimations of iron requirements are derived from factorial estimates based on healthy, iron-sufficient "model" children using data derived mainly from adults. OBJECTIVES In this study, we aimed to quantify iron absorption, loss, and balance in apparently healthy 5- to 7-y-old children living in rural Africa. METHODS We directly measured long-term iron absorption and iron loss in a 2-y observational study in Malawian children (n = 48) using a novel stable iron isotope method. RESULTS Of the 36 children with height-for-age and weight-for-age z scores ≥-2, 13 (36%) were iron deficient (soluble transferrin receptor >8.3 mg/L) and 23 were iron sufficient. Iron-deficient children weighed more than iron-sufficient children [mean difference (95% CI): +2.1 (1.4, 2.7) kg; P = 0.01]. Mean iron losses did not differ significantly between iron-deficient and iron-sufficient children and were comparable to WHO/FAO median estimates of 19 µg/(d × kg). In iron-sufficient children, median (95% CI) dietary iron absorption was 32 (28, 34) µg/(d × kg), comparable to WHO/FAO-estimated median requirements of 32 µg/(d × kg). In iron-deficient children, absorption of 28 (25, 30) µg/(d × kg) was not increased to correct their iron deficit, likely because of a lack of bioavailable dietary iron. Twelve children (25%) were undernourished (underweight, stunted, or both). CONCLUSIONS Our results suggest that WHO/FAO iron requirements are adequate for healthy iron-sufficient children in this rural area of Malawi, but iron-deficient children require additional bioavailable iron to correct their iron deficit.
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Affiliation(s)
- Cornelia Speich
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, ETH Zürich, Zurich, Switzerland
| | - Gary M Brittenham
- Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Colin I Cercamondi
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, ETH Zürich, Zurich, Switzerland
| | - Christophe Zeder
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, ETH Zürich, Zurich, Switzerland
| | - Thandile Nkosi-Gondwe
- Training and Research Unit of Excellence, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Kamija S Phiri
- Training and Research Unit of Excellence, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Diego Moretti
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, ETH Zürich, Zurich, Switzerland.,Nutrition Group, Health Department, Swiss Distance University of Applied Sciences, Regensdorf, Switzerland
| | - Michael B Zimmermann
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, ETH Zürich, Zurich, Switzerland
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14
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The critical roles of iron during the journey from fetus to adolescent: Developmental aspects of iron homeostasis. Blood Rev 2021; 50:100866. [PMID: 34284901 DOI: 10.1016/j.blre.2021.100866] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/28/2021] [Accepted: 07/01/2021] [Indexed: 12/12/2022]
Abstract
Iron is indispensable for human life. However, it is also potentially toxic, since it catalyzes the formation of harmful oxidative radicals in unbound form and may facilitate pathogen growth. Therefore, iron homeostasis needs to be tightly regulated. Rapid growth and development require large amounts of iron, while (especially young) children are vulnerable to infections with iron-dependent pathogens due to an immature immune system. Moreover, unbalanced iron status early in life may have effects on the nervous system, immune system and gut microbiota that persist into adulthood. In this narrative review, we assess the critical roles of iron for growth and development and elaborate how the body adapts to physiologically high iron demands during the journey from fetus to adolescent. As a first step towards the development of clinical guidelines for the management of iron disorders in children, we summarize the unmet needs regarding the developmental aspects of iron homeostasis.
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15
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James PT, Ali Z, Armitage AE, Bonell A, Cerami C, Drakesmith H, Jobe M, Jones KS, Liew Z, Moore SE, Morales-Berstein F, Nabwera HM, Nadjm B, Pasricha SR, Scheelbeek P, Silver MJ, Teh MR, Prentice AM. The Role of Nutrition in COVID-19 Susceptibility and Severity of Disease: A Systematic Review. J Nutr 2021; 151:1854-1878. [PMID: 33982105 PMCID: PMC8194602 DOI: 10.1093/jn/nxab059] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 12/22/2020] [Accepted: 02/17/2021] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Many nutrients have powerful immunomodulatory actions with the potential to alter susceptibility to coronavirus disease 2019 (COVID-19) infection, progression to symptoms, likelihood of severe disease, and survival. OBJECTIVE The aim was to review the latest evidence on how malnutrition across all its forms (under- and overnutrition and micronutrient status) may influence both susceptibility to, and progression of, COVID-19. METHODS We synthesized information on 13 nutrition-related components and their potential interactions with COVID-19: overweight, obesity, and diabetes; protein-energy malnutrition; anemia; vitamins A, C, D, and E; PUFAs; iron; selenium; zinc; antioxidants; and nutritional support. For each section we provide: 1) a landscape review of pertinent material; 2) a systematic search of the literature in PubMed and EMBASE databases, including a wide range of preprint servers; and 3) a screen of 6 clinical trial registries. All original research was considered, without restriction to study design, and included if it covered: 1) severe acute respiratory syndrome coronavirus (CoV) 2 (SARS-CoV-2), Middle East respiratory syndrome CoV (MERS-CoV), or SARS-CoV viruses and 2) disease susceptibility or 3) disease progression, and 4) the nutritional component of interest. Searches took place between 16 May and 11 August 2020. RESULTS Across the 13 searches, 2732 articles from PubMed and EMBASE, 4164 articles from the preprint servers, and 433 trials were returned. In the final narrative synthesis, we include 22 published articles, 38 preprint articles, and 79 trials. CONCLUSIONS Currently there is limited evidence that high-dose supplements of micronutrients will either prevent severe disease or speed up recovery. However, results of clinical trials are eagerly awaited. Given the known impacts of all forms of malnutrition on the immune system, public health strategies to reduce micronutrient deficiencies and undernutrition remain of critical importance. Furthermore, there is strong evidence that prevention of obesity and type 2 diabetes will reduce the risk of serious COVID-19 outcomes. This review is registered at PROSPERO as CRD42020186194.
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Affiliation(s)
- Philip T James
- Department of Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Zakari Ali
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Andrew E Armitage
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Ana Bonell
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Carla Cerami
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Hal Drakesmith
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Modou Jobe
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Kerry S Jones
- National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) Nutritional Biomarker Laboratory, MRC Epidemiology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Zara Liew
- Department of Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Sophie E Moore
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, The Gambia
- Department of Women and Children's Health, King's College London, London, United Kingdom
| | - Fernanda Morales-Berstein
- Department of Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Helen M Nabwera
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Behzad Nadjm
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Sant-Rayn Pasricha
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Australia
| | - Pauline Scheelbeek
- Department of Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Centre on Climate Change and Planetary Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Matt J Silver
- MRC Unit The Gambia at the London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Megan R Teh
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Andrew M Prentice
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, The Gambia
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16
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Berglund SK, Domellöf M. Iron deficiency in infancy: current insights. Curr Opin Clin Nutr Metab Care 2021; 24:240-245. [PMID: 33656466 DOI: 10.1097/mco.0000000000000749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE OF REVIEW Iron deficiency is the most common micronutrient deficiency and infants are at particular risk. The purpose of this review is to summarize recent studies that explored the metabolism of iron in infants as well as the risks and benefits of iron supplementation in different populations. RECENT FINDINGS The ability of infants to regulate iron homeostasis is not fully known but most likely different from adults. Reducing iron deficiency has beneficial effects on neurodevelopment but iron overload may have adverse functional effects including diarrhea and even poor neurodevelopment. Recent studies have confirmed benefits of delayed cord clamping and supplementation of infants in risk groups while iron supplementation to pregnant women has shown limited effect in the offspring with regard to iron status and neurodevelopment. Further support is given to the recommendation that exclusive breast feeding, without supplementation, is safe for normal birth weight infants until 6 months whereafter an iron-rich diet should be given. SUMMARY Iron deficiency negatively impacts global health but efforts to identify optimal interventions are progressing. Yet, questions remain, particularly regarding long-term risks, benefits and optimal interventions for low birth weight infants as well as the level of iron fortification in infant formula.
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Affiliation(s)
- Staffan K Berglund
- Department of Clinical Sciences, Pediatrics
- Wallenberg Centre for Molecular Medicine (WCMM), Umeå University, Umeå, Sweden
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17
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Muriuki JM, Mentzer AJ, Mitchell R, Webb EL, Etyang AO, Kyobutungi C, Morovat A, Kimita W, Ndungu FM, Macharia AW, Ngetsa CJ, Makale J, Lule SA, Musani SK, Raffield LM, Cutland CL, Sirima SB, Diarra A, Tiono AB, Fried M, Gwamaka M, Adu-Afarwuah S, Wirth JP, Wegmüller R, Madhi SA, Snow RW, Hill AVS, Rockett KA, Sandhu MS, Kwiatkowski DP, Prentice AM, Byrd KA, Ndjebayi A, Stewart CP, Engle-Stone R, Green TJ, Karakochuk CD, Suchdev PS, Bejon P, Duffy PE, Davey Smith G, Elliott AM, Williams TN, Atkinson SH. Malaria is a cause of iron deficiency in African children. Nat Med 2021; 27:653-658. [PMID: 33619371 PMCID: PMC7610676 DOI: 10.1038/s41591-021-01238-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 01/12/2021] [Indexed: 12/12/2022]
Abstract
Malaria and iron deficiency (ID) are common and interrelated public health problems in African children. Observational data suggest that interrupting malaria transmission reduces the prevalence of ID1. To test the hypothesis that malaria might cause ID, we used sickle cell trait (HbAS, rs334 ), a genetic variant that confers specific protection against malaria2, as an instrumental variable in Mendelian randomization analyses. HbAS was associated with a 30% reduction in ID among children living in malaria-endemic countries in Africa (n = 7,453), but not among individuals living in malaria-free areas (n = 3,818). Genetically predicted malaria risk was associated with an odds ratio of 2.65 for ID per unit increase in the log incidence rate of malaria. This suggests that an intervention that halves the risk of malaria episodes would reduce the prevalence of ID in African children by 49%.
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Affiliation(s)
- John Muthii Muriuki
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.
- Open University, KEMRI-Wellcome Trust Research Programme, Accredited Research Centre, Kilifi, Kenya.
| | - Alexander J Mentzer
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
| | - Ruth Mitchell
- Medical Research Council (MRC) Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Emily L Webb
- MRC Tropical Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Anthony O Etyang
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Alireza Morovat
- Department of Clinical Biochemistry, Oxford University Hospitals, Oxford, UK
| | - Wandia Kimita
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Francis M Ndungu
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Alex W Macharia
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Caroline J Ngetsa
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Johnstone Makale
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Swaib A Lule
- MRC/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Solomon K Musani
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
| | - Laura M Raffield
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - Clare L Cutland
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Sodiomon B Sirima
- Groupe de Recherche Action en Sante (GRAS), 06 BP 10248, Ouagadougou, Burkina Faso
| | - Amidou Diarra
- Groupe de Recherche Action en Sante (GRAS), 06 BP 10248, Ouagadougou, Burkina Faso
| | - Alfred B Tiono
- Groupe de Recherche Action en Sante (GRAS), 06 BP 10248, Ouagadougou, Burkina Faso
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Moses Gwamaka
- Mother Offspring Malaria Studies (MOMS) Project, Seattle Biomedical Research Institute, Seattle, WA, USA
- Muheza Designated District Hospital, Muheza, Tanzania
- University of Dar es Salaam, Mbeya College of Health and Allied Sciences, Mbeya, Tanzania
| | - Seth Adu-Afarwuah
- Department of Nutrition and Food Science, University of Ghana, Legon, Ghana
| | | | | | - Shabir A Madhi
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Robert W Snow
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Adrian V S Hill
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Centre for Clinical Vaccinology and Tropical Medicine and the Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Kirk A Rockett
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Wellcome Sanger Institute, Hinxton, UK
| | | | - Dominic P Kwiatkowski
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
- Wellcome Sanger Institute, Hinxton, UK
| | - Andrew M Prentice
- MRC Unit The Gambia at London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | | | | | | | - Reina Engle-Stone
- Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Tim J Green
- SAHMRi Women and Kids, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
- School of Medicine, The University of Adelaide, Adelaide, South Australia, Australia
| | - Crystal D Karakochuk
- Food, Nutrition, and Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Parminder S Suchdev
- Department of Pediatrics, Emory University and Emory Global Health Institute, Atlanta, GA, USA
| | - Philip Bejon
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - George Davey Smith
- Medical Research Council (MRC) Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Alison M Elliott
- MRC/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, UK
| | - Thomas N Williams
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Department of Infectious Diseases and Institute of Global Health Innovation, Imperial College, London, UK
| | - Sarah H Atkinson
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Department of Paediatrics, University of Oxford, Oxford, UK.
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18
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Frost JN, Tan TK, Abbas M, Wideman SK, Bonadonna M, Stoffel NU, Wray K, Kronsteiner B, Smits G, Campagna DR, Duarte TL, Lopes JM, Shah A, Armitage AE, Arezes J, Lim PJ, Preston AE, Ahern D, Teh M, Naylor C, Salio M, Gileadi U, Andrews SC, Dunachie SJ, Zimmermann MB, van der Klis FR, Cerundolo V, Bannard O, Draper SJ, Townsend AR, Galy B, Fleming MD, Lewis MC, Drakesmith H. Hepcidin-Mediated Hypoferremia Disrupts Immune Responses to Vaccination and Infection. MED 2021; 2:164-179.e12. [PMID: 33665641 PMCID: PMC7895906 DOI: 10.1016/j.medj.2020.10.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/26/2020] [Accepted: 10/16/2020] [Indexed: 01/09/2023]
Abstract
BACKGROUND How specific nutrients influence adaptive immunity is of broad interest. Iron deficiency is the most common micronutrient deficiency worldwide and imparts a significant burden of global disease; however, its effects on immunity remain unclear. METHODS We used a hepcidin mimetic and several genetic models to examine the effect of low iron availability on T cells in vitro and on immune responses to vaccines and viral infection in mice. We examined humoral immunity in human patients with raised hepcidin and low serum iron caused by mutant TMPRSS6. We tested the effect of iron supplementation on vaccination-induced humoral immunity in piglets, a natural model of iron deficiency. FINDINGS We show that low serum iron (hypoferremia), caused by increased hepcidin, severely impairs effector and memory responses to immunizations. The intensified metabolism of activated lymphocytes requires the support of enhanced iron acquisition, which is facilitated by IRP1/2 and TFRC. Accordingly, providing extra iron improved the response to vaccination in hypoferremic mice and piglets, while conversely, hypoferremic humans with chronically increased hepcidin have reduced concentrations of antibodies specific for certain pathogens. Imposing hypoferremia blunted the T cell, B cell, and neutralizing antibody responses to influenza virus infection in mice, allowing the virus to persist and exacerbating lung inflammation and morbidity. CONCLUSIONS Hypoferremia, a well-conserved physiological innate response to infection, can counteract the development of adaptive immunity. This nutrient trade-off is relevant for understanding and improving immune responses to infections and vaccines in the globally common contexts of iron deficiency and inflammatory disorders. FUNDING Medical Research Council, UK.
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Affiliation(s)
- Joe N. Frost
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Tiong Kit Tan
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Munawar Abbas
- Food and Nutritional Sciences, School of Chemistry, Food, and Pharmacy, University of Reading, Reading, UK
| | - Sarah K. Wideman
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Michael Bonadonna
- Division of Virus-Associated Carcinogenesis (F170), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Nicole U. Stoffel
- ETH Zurich, Human Nutrition Laboratory, Institute of Food, Nutrition, and Health, Zurich, Switzerland
| | - Katherine Wray
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Barbara Kronsteiner
- Centre for Tropical Medicine and Global Health, and Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
| | - Gaby Smits
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Dean R. Campagna
- Department of Pathology, Boston Children’s Hospital and Harvard Medical School, Boston, MA, USA
| | - Tiago L. Duarte
- Instituto de Biologia Molecular e Celular & Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Porto, Portugal
| | - José M. Lopes
- Faculty of Medicine (FMUP) and Institute of Molecular Pathology and Immunology (IPATIMUP), University of Porto, Porto, Portugal
| | - Akshay Shah
- Radcliffe Department of Medicine, University of Oxford and John Radcliffe Hospital, Oxford, UK
| | - Andrew E. Armitage
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - João Arezes
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Pei Jin Lim
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Alexandra E. Preston
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - David Ahern
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Megan Teh
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Caitlin Naylor
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Mariolina Salio
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Uzi Gileadi
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Simon C. Andrews
- School of Biological Sciences, University of Reading, Reading, UK
| | - Susanna J. Dunachie
- Centre for Tropical Medicine and Global Health, and Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
| | - Michael B. Zimmermann
- ETH Zurich, Human Nutrition Laboratory, Institute of Food, Nutrition, and Health, Zurich, Switzerland
| | - Fiona R.M. van der Klis
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Vincenzo Cerundolo
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Oliver Bannard
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | | | - Alain R.M. Townsend
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Bruno Galy
- Division of Virus-Associated Carcinogenesis (F170), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Mark D. Fleming
- Department of Pathology, Boston Children’s Hospital and Harvard Medical School, Boston, MA, USA
| | - Marie C. Lewis
- Food and Nutritional Sciences, School of Chemistry, Food, and Pharmacy, University of Reading, Reading, UK
| | - Hal Drakesmith
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
- Haematology Theme, Oxford Biomedical Research Centre, Oxford, UK
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19
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Joof F, Goheen MM, Cerami C. Artemisinin Activity in Red Blood Cells from Anemic Children. Am J Trop Med Hyg 2021; 104:271-275. [PMID: 33169662 DOI: 10.4269/ajtmh.20-0304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Artemisinin combination therapies are the current frontline therapy for falciparum malaria. Artemisinin is activated by heme iron, and the consequent production of reactive oxygen species and carbon-centered radicals results in rapid parasite clearance. Red blood cells (RBCs) from anemic iron-deficient individuals have decreased levels of heme, and such deficiencies are highly prevalent among children and pregnant women in malaria-endemic countries. We, therefore, investigated the possibility that host anemia could impair artemisinin activity and alter the drug sensitivity of artemisinin-resistant strains of Plasmodium falciparum. We collected RBCs from anemic (n = 35) and nonanemic (n = 11) Gambian children between the ages of 2 and 24 months. Parasites grown in RBCs from both groups were assessed in vitro using the ring-stage survival assay with artemisinin-resistant and artemisinin-sensitive strains of P. falciparum. No differences were found in artemisinin sensitivity (P > 0.05), and there was no correlation between artemisinin activity and host hemoglobin levels. Standard antimalarial drug activity assays for representatives of the major classes of antimalarial drugs found no differences in the IC50 values against P. falciparum between anemic and nonanemic RBCs. We conclude that host anemia does not influence artemisinin activity.
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Affiliation(s)
- Fatou Joof
- 1Medical Research Council Unit The Gambia at London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Morgan M Goheen
- 2Department of Internal Medicine, Yale University, New Haven, Connecticut
| | - Carla Cerami
- 1Medical Research Council Unit The Gambia at London School of Hygiene and Tropical Medicine, Banjul, The Gambia
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20
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Mendoza E, Duque X, Moran S, Martínez-Andrade G, Reyes-Maldonado E, Flores-Huerta S, Martinez H. Hepcidin and other indicators of iron status, by alpha-1 acid glycoprotein levels, in a cohort of Mexican infants. Ann Hematol 2021; 100:879-890. [PMID: 33515046 DOI: 10.1007/s00277-021-04402-5] [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: 08/17/2020] [Accepted: 01/03/2021] [Indexed: 11/25/2022]
Abstract
The purpose of this study was to describe the changes in iron status indicators at 6 and 12 months of age, controlling by inflammation by measuring alpha-1 acid glycoprotein (AGP). This longitudinal study included 48 healthy-term singleton infants with birth weight ≥ 2500 g, born in hospitals of the Mexican Institute for Social Security. Complete blood count, ferritin, soluble transferrin receptor (sTfR), hepcidin, and AGP were measured in blood at 6 and 12 months of age. sTfR/ferritin ratio and total body iron (TBI) stores were calculated. Hemoglobin and sTfR/ferritin ratio increased with age, while ferritin and TBI decreased. In infants without inflammation, hepcidin, sTfR, and MVC did not show significant changes from 6 to 12 months of age, while ferritin and TBI decreased. In infants with inflammation, hepcidin, TBI, and ferritin levels increased, while hemoglobin and sTfR/ferritin ratio decreased. MVC and sTfR did not change significantly in the presence or absence of inflammation. Hepcidin concentration correlated positively and significantly with ferritin and TBI stores and showed significant negative correlation with sTfR/ferritin ratio. Our study showed that, in absence of inflammation and ID, during the first year of life, physiological changes occur in hemoglobin and ferritin levels as well as in indicators derived from ferritin and sTfR; in contrast, hepcidin and sTfR did not show significant change. However, hepcidin concentration was lower in infants with ID and was higher when inflammation was present, supporting that infants have a functional hepcidin response to changes in iron stores.
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Affiliation(s)
- Eugenia Mendoza
- Infectious Diseases Research Unit, Pediatric Hospital, Mexican Institute for Social Security, 06720, Mexico City, Mexico
| | - Ximena Duque
- Infectious Diseases Research Unit, Pediatric Hospital, Mexican Institute for Social Security, 06720, Mexico City, Mexico.
| | - Segundo Moran
- Gastroenterology Research Laboratory, Mexican Institute for Social Security, 06720, Mexico City, Mexico
| | - Gloria Martínez-Andrade
- Research Unit in Epidemiology and Health Services, Mexican Institute for Social Security, 06720, Mexico City, Mexico
| | - Elba Reyes-Maldonado
- Morphology Department, National School of Biological Sciences, Instituto Politécnico Nacional, 01135, Mexico City, Mexico
| | - Samuel Flores-Huerta
- Research Department of Community Health, Hospital Infantil de México "Federico Gómez", 06720, Mexico City, Mexico
| | - Homero Martinez
- Dirección de Investigación, Hospital Infantil de México "Federico Gómez", 06720, Mexico City, Mexico
- Global Technical Services-NTEAM, Nutrition International, Ottawa, ON, K2P 2K3, Canada
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21
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Pasricha SR, Tye-Din J, Muckenthaler MU, Swinkels DW. Iron deficiency. Lancet 2021; 397:233-248. [PMID: 33285139 DOI: 10.1016/s0140-6736(20)32594-0] [Citation(s) in RCA: 325] [Impact Index Per Article: 108.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 07/06/2020] [Accepted: 07/10/2020] [Indexed: 02/06/2023]
Abstract
Iron deficiency is one of the leading contributors to the global burden of disease, and particularly affects children, premenopausal women, and people in low-income and middle-income countries. Anaemia is one of many consequences of iron deficiency, and clinical and functional impairments can occur in the absence of anaemia. Iron deprivation from erythroblasts and other tissues occurs when total body stores of iron are low or when inflammation causes withholding of iron from the plasma, particularly through the action of hepcidin, the main regulator of systemic iron homoeostasis. Oral iron therapy is the first line of treatment in most cases. Hepcidin upregulation by oral iron supplementation limits the absorption efficiency of high-dose oral iron supplementation, and of oral iron during inflammation. Modern parenteral iron formulations have substantially altered iron treatment and enable rapid, safe total-dose iron replacement. An underlying cause should be sought in all patients presenting with iron deficiency: screening for coeliac disease should be considered routinely, and endoscopic investigation to exclude bleeding gastrointestinal lesions is warranted in men and postmenopausal women presenting with iron deficiency anaemia. Iron supplementation programmes in low-income countries comprise part of the solution to meeting WHO Global Nutrition Targets.
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Affiliation(s)
- Sant-Rayn Pasricha
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Diagnostic Haematology, The Royal Melbourne Hospital, Parkville, VIC, Australia; Department of Clinical Haematology, Peter MacCallum Cancer Centre and The Royal Melbourne Hospital, Melbourne, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
| | - Jason Tye-Din
- Immunology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Gastroenterology, The Royal Melbourne Hospital, Parkville, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Martina U Muckenthaler
- Department of Pediatric Oncology, Hematology, and Immunology and Molecular Medicine Partnership Unit, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, European Molecular Biology Laboratory, Heidelberg, Germany; Translational Lung Research Center, German Center for Lung Research, Heidelberg, Germany; German Centre for Cardiovascular Research, Partner Site Heidelberg, Mannheim, Germany
| | - Dorine W Swinkels
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
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22
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Inflammatory Markers and Hepcidin are Elevated but Serum Iron is Lower in Obese Women of Reproductive Age. Nutrients 2021; 13:nu13010217. [PMID: 33466578 PMCID: PMC7828682 DOI: 10.3390/nu13010217] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 11/17/2022] Open
Abstract
Limited evidence suggests that serum iron and hepcidin concentrations are dysregulated in obesity and inflammation. The objective of the present study was to compare C-reactive protein, interleukin-6, circulating levels of hepcidin, serum lipids, and iron status in obese vs. normal-weight women of childbearing age. Healthy women aged 18–30 years were recruited for the study (n = 47: 25 obese and 22 normal weight). Fasting blood samples were obtained to measure serum lipids (total cholesterol, HDL, LDL cholesterol, triglycerides, non-HDL cholesterol), complete blood count, serum iron, total iron-binding capacity, transferrin saturation, serum ferritin, hepcidin, C-reactive protein, and interleukin-6. Obese women had significantly higher mean serum C-reactive protein (p < 0.001), interleukin-6 (p < 0.001), hepcidin (p = 0.024), triglycerides (p < 0.001) and total cholesterol/HDL ratio (p < 0.001) but lower HDL (p = 0.001) and serum iron/hepcidin ratio (p = 0.011) compared with normal-weight women. BMI correlated positively with inflammatory markers, triglycerides, LDL and total cholesterol/HDL ratio, and negatively with HDL and serum iron/hepcidin ratio. Serum iron correlated negatively with ferritin in the obese group (p = 0.030) but positively in normal weight women (p = 0.002). BMI and ferritin were the only predictors of serum iron/hepcidin ratio accounting for 23% of the variation among subjects. Studies are needed to examine anti-inflammatory dietary approaches that can improve iron biomarkers in obese women.
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23
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Menshawey R, Menshawey E, Alserr AHK, Abdelmassih AF. Low iron mitigates viral survival: insights from evolution, genetics, and pandemics-a review of current hypothesis. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2020; 21:75. [PMID: 38624521 PMCID: PMC7738201 DOI: 10.1186/s43042-020-00114-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/20/2020] [Indexed: 12/21/2022] Open
Abstract
Background Upon re-examination of our human history, evolutionary perspectives, and genetics, a prevailing iron deficiency phenotype appears to have evolved to protect the human race from extinction. Body In this review, we summarize the evolutionary and genetic perspectives pointing towards the hypothesis that low iron mitigates infection. The presence of infection promotes the generation of resistance alleles, and there are some evolutionary and genetic clues that suggest the presence of an iron deficiency phenotype that may have developed to protect against infection. Examples include the relative paucity of iron overload genes given the essential role of iron, as well as the persistence of iron deficiency among populations in spite of public health efforts to treat it. Additional examination of geographic areas with severe iron deficiency in the setting of pandemics including H1N1, SARS, and COVID-19 reveals that areas with higher prevalence of iron deficiency are less affected. RNA viruses have several evolutionary adaptations which suggest their absolute need for iron, and this dependency may be exploited during treatment. Conclusion RNA viruses pose a unique challenge to modern healthcare, with an average of 2-3 new pathogens being discovered yearly. Their overarching requirements for iron, along with human evolutionary and genetic adaptations which favored an iron deficiency phenotype, ultimately suggest the potential need for iron control in these infections.
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Affiliation(s)
- Rahma Menshawey
- Faculty of Medicine, Kasr al Ainy, Cairo University, Geziret Elroda, Manial, Cairo, 11562 Egypt
| | - Esraa Menshawey
- Faculty of Medicine, Kasr al Ainy, Cairo University, Geziret Elroda, Manial, Cairo, 11562 Egypt
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24
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Baldi AJ, Clucas D, Pasricha SR. Anemia and water, sanitation, and hygiene (WASH)-is there really a link? Am J Clin Nutr 2020; 112:1145-1146. [PMID: 32692804 DOI: 10.1093/ajcn/nqaa213] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Andrew J Baldi
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Danielle Clucas
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia.,Diagnostic Haematology, The Royal Melbourne Hospital, Victoria, Australia
| | - Sant-Rayn Pasricha
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia.,Diagnostic Haematology, The Royal Melbourne Hospital, Victoria, Australia.,Clinical Haematology at the Peter MacCallum Cancer Centre and The Royal Melbourne Hospital, Parkville Victoria, Australia
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25
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Uyoga MA, Mikulic N, Paganini D, Mwasi E, Stoffel NU, Zeder C, Karanja S, Zimmermann MB. The effect of iron dosing schedules on plasma hepcidin and iron absorption in Kenyan infants. Am J Clin Nutr 2020; 112:1132-1141. [PMID: 32678434 DOI: 10.1093/ajcn/nqaa174] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 06/11/2020] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND In adults, oral iron doses increase plasma hepcidin (PHep) for 24 h, but not for 48 h, and there is a circadian increase in PHep over the day. Because high PHep decreases fractional iron absorption (FIA), alternate day iron dosing in the morning may be preferable to consecutive day dosing. Whether these effects occur in infants is uncertain. OBJECTIVE Using stable iron isotopes in Kenyan infants, we compared FIA from morning and afternoon doses and from consecutive, alternate (every second day) and every third day iron doses. METHODS In prospective studies, we measured and compared FIA and the PHep response from 1) meals fortified with a 12-mg iron micronutrient powder given in the morning or afternoon (n = 22); 2) the same given on consecutive or alternate days (n = 21); and 3) a 12-mg iron supplement given on alternate days or every third day (n = 24). RESULTS In total, 65.7% of infants were anemic. In study 1, PHep did not differ between morning and afternoon (P = 0.072), and geometric mean FIA[-SD, +SD](%) did not differ between the morning and afternoon doses [15.9 (8.9, 28.6) and 16.1 (8.7, 29.8), P = 0.877]. In study 2, PHep was increased 24 h after oral iron (P = 0.014), and mean FIA [±SD](%) from the baseline dose [23.3 (10.9)] was greater than that from the consecutive day dose (at 24 h) [20.1 (10.4); P = 0.042] but did not differ from the alternate day dose (at 48 h) [20.9 (13.4); P = 0.145]. In study 3, PHep was not increased 48 and 72 h after oral iron (P = 0.384), and the geometric mean FIA[-SD, +SD](%) from doses given at baseline, alternate days, and every third day did not differ [12.7 (7.3, 21.9), 13.8 (7.8, 24.2), and 14.8 (8.8, 24.8), respectively; P = 0.080]. CONCLUSIONS In Kenyan infants given 12 mg oral iron, morning and afternoon doses are comparably absorbed, dosing on consecutive days increases PHep and modestly decreases iron absorption compared with alternate day dosing, and dosing on alternate days or every third day does not increase PHep or decrease absorption. This trial was registered at clinicaltrials.gov as NCT02989311 and NCT03617575.
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Affiliation(s)
- Mary A Uyoga
- Laboratory of Human Nutrition, ETH Zurich, Switzerland
| | - Nadja Mikulic
- Laboratory of Human Nutrition, ETH Zurich, Switzerland
| | | | - Edith Mwasi
- Pediatric Department, Msambweni County Referral Hospital, Msambweni, Kenya
| | | | | | - Simon Karanja
- Public and Community Health Department, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
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26
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Suchdev PS, Trehan I. Optimizing iron supplementation for children with severe malaria. Am J Clin Nutr 2020; 111:939-940. [PMID: 32140703 DOI: 10.1093/ajcn/nqaa041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Parminder S Suchdev
- Department of Pediatrics, Emory University, Atlanta, GA, USA.,Emory Global Health Institute, Emory University, Atlanta, GA, USA
| | - Indi Trehan
- Department of Pediatrics, University of Washington, Seattle, WA, USA.,Department of Global Health, University of Washington, Seattle, WA, USA
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27
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Donker AE, Galesloot TE, Laarakkers CM, Klaver SM, Bakkeren DL, Swinkels DW. Standardized serum hepcidin values in Dutch children: Set point relative to body iron changes during childhood. Pediatr Blood Cancer 2020; 67:e28038. [PMID: 31724793 DOI: 10.1002/pbc.28038] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 09/13/2019] [Accepted: 09/23/2019] [Indexed: 12/23/2022]
Abstract
BACKGROUND Use of serum hepcidin measurements in pediatrics would benefit from standardized age- and sex-specific reference ranges in children, in order to enable the establishment of clinical decision limits that are universally applicable. PROCEDURE We measured serum hepcidin-25 levels in 266 healthy Dutch children aged 0.3-17 years, using an isotope dilution mass spectrometry assay, standardized with our commutable secondary reference material (RM), assigned by a candidate primary RM. RESULTS We constructed age- and sex-specific values for serum hepcidin and its ratio with ferritin and transferrin saturation (TSAT). Serum hepcidin levels and hepcidin/ferritin and TSAT/hepcidin ratios were similar for both sexes. Serum hepcidin and hepcidin/ferritin ratio substantially declined after the age of 12 years and TSAT/hepcidin ratio gradually increased with increasing age. Serum hepcidin values for Dutch children <12 years (n = 170) and >12 years (n = 96) were 1.9 nmol/L (median); 0.1-13.1 nmol/L (p2.5-p97.5) and 0.9 nmol/L; 0.0-9.1 nmol/L, respectively. Serum ferritin was the most significant correlate of serum hepcidin in our study population, explaining 15.1% and 7.9% of variance in males and females, respectively. Multivariable linear regression analysis including age, blood sampling time, iron parameters, ALT, CRP, and body mass index as independent variables showed a statistically significant negative association between age as a dichotomous variable (≤12 vs >12 years) and log-transformed serum hepcidin levels in both sexes. CONCLUSIONS We demonstrate that serum hepcidin relative to indicators of body iron is age dependent in children, suggesting that the set point of serum hepcidin relative to stored and circulating iron changes during childhood.
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Affiliation(s)
- Albertine E Donker
- Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Pediatrics, Máxima Medical Center, Veldhoven, The Netherlands
| | - Tessel E Galesloot
- Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Coby M Laarakkers
- Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Translational Metabolic Laboratory (TML, 830), Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Siem M Klaver
- Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Translational Metabolic Laboratory (TML, 830), Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Dirk L Bakkeren
- Department of Clinical Chemistry, Máxima Medical Center , Veldhoven, The Netherlands
| | - Dorine W Swinkels
- Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Translational Metabolic Laboratory (TML, 830), Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
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Armitage AE, Moretti D. The Importance of Iron Status for Young Children in Low- and Middle-Income Countries: A Narrative Review. Pharmaceuticals (Basel) 2019; 12:E59. [PMID: 30995720 PMCID: PMC6631790 DOI: 10.3390/ph12020059] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/09/2019] [Accepted: 04/12/2019] [Indexed: 12/21/2022] Open
Abstract
Early childhood is characterised by high physiological iron demand to support processes including blood volume expansion, brain development and tissue growth. Iron is also required for other essential functions including the generation of effective immune responses. Adequate iron status is therefore a prerequisite for optimal child development, yet nutritional iron deficiency and inflammation-related iron restriction are widespread amongst young children in low- and middle-income countries (LMICs), meaning iron demands are frequently not met. Consequently, therapeutic iron interventions are commonly recommended. However, iron also influences infection pathogenesis: iron deficiency reduces the risk of malaria, while therapeutic iron may increase susceptibility to malaria, respiratory and gastrointestinal infections, besides reshaping the intestinal microbiome. This means caution should be employed in administering iron interventions to young children in LMIC settings with high infection burdens. In this narrative review, we first examine demand and supply of iron during early childhood, in relation to the molecular understanding of systemic iron control. We then evaluate the importance of iron for distinct aspects of physiology and development, particularly focusing on young LMIC children. We finally discuss the implications and potential for interventions aimed at improving iron status whilst minimising infection-related risks in such settings. Optimal iron intervention strategies will likely need to be individually or setting-specifically adapted according to iron deficiency, inflammation status and infection risk, while maximising iron bioavailability and considering the trade-offs between benefits and risks for different aspects of physiology. The effectiveness of alternative approaches not centred around nutritional iron interventions for children should also be thoroughly evaluated: these include direct targeting of common causes of infection/inflammation, and maternal iron administration during pregnancy.
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Affiliation(s)
- Andrew E Armitage
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DS, UK.
| | - Diego Moretti
- Laboratory of Human Nutrition, Institute of Food Nutrition and Health, Department of Health Sciences and Technology, ETH Zürich, CH-8092 Zürich, Switzerland.
- Nutrition Group, Health Department, Swiss Distance University of Applied Sciences, CH-8105 Regensdorf, Switzerland.
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