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McMillen SA, Dean R, Dihardja E, Ji P, Lönnerdal B. Benefits and Risks of Early Life Iron Supplementation. Nutrients 2022; 14:4380. [PMID: 36297062 PMCID: PMC9608469 DOI: 10.3390/nu14204380] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/16/2022] [Accepted: 10/17/2022] [Indexed: 01/19/2024] Open
Abstract
Infants are frequently supplemented with iron to prevent iron deficiency, but iron supplements may have adverse effects on infant health. Although iron supplements can be highly effective at improving iron status and preventing iron deficiency anemia, iron may adversely affect growth and development, and may increase risk for certain infections. Several reviews exist in this area; however, none has fully summarized all reported outcomes of iron supplementation during infancy. In this review, we summarize the risks and benefits of iron supplementation as they have been reported in controlled studies and in relevant animal models. Additionally, we discuss the mechanisms that may underly beneficial and adverse effects.
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Affiliation(s)
| | | | | | | | - Bo Lönnerdal
- Department of Nutrition, University of California, Davis, CA 95616, USA
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Donley DW, Realing M, Gigley JP, Fox JH. Iron activates microglia and directly stimulates indoleamine-2,3-dioxygenase activity in the N171-82Q mouse model of Huntington's disease. PLoS One 2021; 16:e0250606. [PMID: 33989290 PMCID: PMC8121302 DOI: 10.1371/journal.pone.0250606] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 04/10/2021] [Indexed: 01/05/2023] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disorder caused by a dominant CAG-repeat expansion in the huntingtin gene. Microglial activation is a key feature of HD pathology, and is present before clinical disease onset. The kynurenine pathway (KP) of tryptophan degradation is activated in HD, and is thought to contribute to disease progression. Indoleamine-2,3-dioxygenase (IDO) catalyzes the first step in this pathway; this and other pathway enzymes reside with microglia. While HD brain microglia accumulate iron, the role of iron in promoting microglial activation and KP activity is unclear. Here we utilized the neonatal iron supplementation model to investigate the relationship between iron, microglial activation and neurodegeneration in adult HD mice. We show in the N171-82Q mouse model of HD microglial morphologic changes consistent with immune activation. Neonatal iron supplementation in these mice promoted neurodegeneration and resulted in additional microglial activation in adults as determined by increased soma volume and decreased process length. We further demonstrate that iron activates IDO, both in brain lysates and purified recombinant protein (EC50 = 1.24 nM). Brain IDO activity is increased by HD. Neonatal iron supplementation further promoted IDO activity in cerebral cortex, altered KP metabolite profiles, and promoted HD neurodegeneration as measured by brain weights and striatal volumes. Our results demonstrate that dietary iron is an important activator of microglia and the KP pathway in this HD model, and that this occurs in part through a direct effect on IDO. The findings are relevant to understanding how iron promotes neurodegeneration in HD.
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Affiliation(s)
- David W. Donley
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY, United States of America
- Neuroscience Graduate Program, University of Wyoming, Laramie, WY, United States of America
| | - Marley Realing
- Microbiology Undergraduate Program, University of Wyoming, Laramie, WY, United States of America
| | - Jason P. Gigley
- Department of Molecular Biology, University of Wyoming, Laramie, WY, United States of America
| | - Jonathan H. Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY, United States of America
- Neuroscience Graduate Program, University of Wyoming, Laramie, WY, United States of America
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Gahagan S, Delker E, Blanco E, Burrows R, Lozoff B. Randomized Controlled Trial of Iron-Fortified versus Low-Iron Infant Formula: Developmental Outcomes at 16 Years. J Pediatr 2019; 212:124-130.e1. [PMID: 31253407 PMCID: PMC7152502 DOI: 10.1016/j.jpeds.2019.05.030] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/28/2019] [Accepted: 05/13/2019] [Indexed: 01/25/2023]
Abstract
OBJECTIVES To test differences in cognitive outcomes among adolescents randomly assigned previously as infants to iron-fortified formula or low-iron formula as part of an iron deficiency anemia prevention trial. STUDY DESIGN Infants were recruited from community clinics in low- to middle-income neighborhoods in Santiago, Chile. Entrance criteria included term, singleton infants; birth weight of ≥3.0 kg; and no major congenital anomalies, perinatal complications, phototherapy, hospitalization >5 days, chronic illness, or iron deficiency anemia at 6 months. Six-month-old infants were randomized to iron-fortified (12 mg/L) or low-iron (2.3 mg/L) formula for 6 months. At 16 years of age, cognitive ability, visual perceptual ability, visual memory, and achievement in math, vocabulary, and comprehension were assessed, using standardized measures. We compared differences in developmental test scores according to randomization group. RESULTS At the follow-up assessment, the 405 participants averaged 16.2 years of age and 46% were male. Those randomized to iron-fortified formula had lower scores than those randomized to low-iron formula for visual memory, arithmetic achievement, and reading comprehension achievement. For visual motor integration, there was an interaction with baseline infancy hemoglobin, such that the iron-fortified group outperformed the low-iron group when 6-month hemoglobin was low and underperformed when 6-month hemoglobin was high. CONCLUSIONS Adolescents who received iron-fortified formula as infants from 6 to 12 months of age at levels recommended in the US had poorer cognitive outcomes compared with those who received a low-iron formula. The prevention of iron deficiency anemia in infancy is important for brain development. However, the optimal level of iron supplementation in infancy is unclear. TRIAL REGISTRATION Clinicaltrials.gov: NCT01166451.
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Affiliation(s)
- Sheila Gahagan
- Department of Pediatrics, Division of Child Development and Community Health, University of California, San Diego, La Jolla, CA; Center for Human Growth and Development and Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI.
| | - Erin Delker
- Department of Pediatrics, Division of Child Development and Community Health, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, USA 92093-0927,Epidemiology, San Diego State University / University of California at San Diego Joint Doctoral Program, 4305 University Avenue, San Diego, CA, USA, 92105
| | - Estela Blanco
- Department of Pediatrics, Division of Child Development and Community Health, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, USA 92093-0927,Public Health, University of Chile, Doctoral Program, Avenida Independencia 939, Santiago, Chile
| | - Raquel Burrows
- Institute of Nutrition and Food Technology, University of Chile, Av. El Líbano 5524, Santiago, Chile
| | - Betsy Lozoff
- Center for Human Growth and Development and Department of Pediatrics and Communicable Diseases, University of Michigan, 300 N. Ingalls Bldg. 1063NE, Ann Arbor, MI 48109
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Agrawal S, Fox JH. Novel proteomic changes in brain mitochondria provide insights into mitochondrial dysfunction in mouse models of Huntington's disease. Mitochondrion 2019; 47:318-329. [PMID: 30902619 DOI: 10.1016/j.mito.2019.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 10/07/2018] [Accepted: 03/18/2019] [Indexed: 12/11/2022]
Abstract
Huntington's disease (HD) is a progressive ultimately fatal disorder caused by a glutamine-encoding CAG expansion in the huntingtin (HTT) gene that results in degeneration mainly in striatal and cerebro-cortical brain regions. Mitochondrial dysfunction is one important facet of HD pathogenesis. Here we used R6/2 and YAC128 HD mouse models of human HD, that express different HTT transgenes and have different progression rates, to identify HD brain mitochondrial proteomic signatures. Cerebral cortical mitochondrial preparations from HD and wild-type litter mate mice were compared by two-dimensional SDS-PAGE electrophoresis and MALDI-TOF/TOF mass spectrometry. Proteomic analyses inferred 17 and 12 differentially expressed proteins, respectively in 12 week R6/2 and 15 month YAC128 HD mice, compared to controls. Peroxiredoxin 3, stress-70, DJ-1, isocitrate dehydrogenase [NAD] α subunit and ATP synthase subunit D were differentially expressed in both models. Using the PANTHER (Protein ANalysis THrough Evolutionary Relationships) classification system we show that the inferred proteins are involved in oxidative stress defense, oxidative phosphorylation, the citric acid cycle, pyruvate metabolism, apoptosis, protein folding and iron metabolism. Common mitochondrial proteomic changes are significant in mouse models of middle (YAC128) and advanced (R6/2) HD despite differences in the HTT transgenes, age, genetic background and disease stage. The findings identify a proteomic signature of HD mitochondria in mouse models that includes previously unrecognized proteins.
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Affiliation(s)
- Sonal Agrawal
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82070, USA
| | - Jonathan H Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82070, USA.
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Niu L, Ye C, Sun Y, Peng T, Yang S, Wang W, Li H. Mutant huntingtin induces iron overload via up-regulating IRP1 in Huntington's disease. Cell Biosci 2018; 8:41. [PMID: 30002810 PMCID: PMC6033216 DOI: 10.1186/s13578-018-0239-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 06/27/2018] [Indexed: 02/06/2023] Open
Abstract
Background Iron accumulation in basal ganglia accompanies neuronal loss in Huntington’s disease (HD) patients and mouse disease models. Disruption of HD brain iron homeostasis occurs before the onset of clinical signs. Therefore, investigating the mechanism of iron accumulation is essential to understanding its role in disease pathogenesis. Methods N171-82Q HD transgenic mice brain iron was detected by using Diaminobenzidine-enhanced Perls’ stain. Iron homeostatic proteins including iron response protein 1 (IRP1), transferrin (Tf), ferritin and transferrin receptor (TfR) were determined by using western blotting and immunohistochemistry, and their relative expression levels of RNA were measured by RT-PCR in both N171-82Q HD transgenic mice and HEK293 cells expressing N-terminal of huntingtin. Results Iron was increased in striatum and cortex of N171-82Q HD transgenic mice. Analysis of iron homeostatic proteins revealed increased expression of IRP1, Tf, ferritin and TfR in N171-82Q mice striatum and cortex. The same results were obtained in HEK293 cells expressing N-terminal of mutant huntingtin containing 160 CAG repeats. Conclusion We conclude that mutant huntingtin may cause abnormal iron homeostatic pathways by increasing IRP1 expression in Huntington’s disease, suggesting potential therapeutic target.
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Affiliation(s)
- Li Niu
- 1Department of Histology and Embryology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030 People's Republic of China
| | - Cuifang Ye
- 1Department of Histology and Embryology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030 People's Republic of China.,2Institute for Brain Sciences, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 People's Republic of China
| | - Yun Sun
- 1Department of Histology and Embryology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030 People's Republic of China
| | - Ting Peng
- 1Department of Histology and Embryology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030 People's Republic of China.,2Institute for Brain Sciences, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 People's Republic of China.,3Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030 People's Republic of China
| | - Shiming Yang
- 1Department of Histology and Embryology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030 People's Republic of China
| | - Weixi Wang
- 1Department of Histology and Embryology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030 People's Republic of China
| | - He Li
- 1Department of Histology and Embryology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030 People's Republic of China.,2Institute for Brain Sciences, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 People's Republic of China.,3Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030 People's Republic of China
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Agrawal S, Fox J, Thyagarajan B, Fox JH. Brain mitochondrial iron accumulates in Huntington's disease, mediates mitochondrial dysfunction, and can be removed pharmacologically. Free Radic Biol Med 2018; 120:317-329. [PMID: 29625173 PMCID: PMC5940499 DOI: 10.1016/j.freeradbiomed.2018.04.002] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/01/2018] [Accepted: 04/02/2018] [Indexed: 01/18/2023]
Abstract
Mitochondrial bioenergetic dysfunction is involved in neurodegeneration in Huntington's disease (HD). Iron is critical for normal mitochondrial bioenergetics but can also contribute to pathogenic oxidation. The accumulation of iron in the brain occurs in mouse models and in human HD. Yet the role of mitochondria-related iron dysregulation as a contributor to bioenergetic pathophysiology in HD is unclear. We demonstrate here that human HD and mouse model HD (12-week R6/2 and 12-month YAC128) brains accumulated mitochondrial iron and showed increased expression of iron uptake protein mitoferrin 2 and decreased iron-sulfur cluster synthesis protein frataxin. Mitochondria-enriched fractions from mouse HD brains had deficits in membrane potential and oxygen uptake and increased lipid peroxidation. In addition, the membrane-permeable iron-selective chelator deferiprone (1 μM) rescued these effects ex-vivo, whereas hydrophilic iron and copper chelators did not. A 10-day oral deferiprone treatment in 9-week R6/2 HD mice indicated that deferiprone removed mitochondrial iron, restored mitochondrial potentials, decreased lipid peroxidation, and improved motor endurance. Neonatal iron supplementation potentiates neurodegeneration in mouse models of HD by unknown mechanisms. We found that neonatal iron supplementation increased brain mitochondrial iron accumulation and potentiated markers of mitochondrial dysfunction in HD mice. Therefore, bi-directional manipulation of mitochondrial iron can potentiate and protect against markers of mouse HD. Our findings thus demonstrate the significance of iron as a mediator of mitochondrial dysfunction and injury in mouse models of human HD and suggest that targeting the iron-mitochondrial pathway may be protective.
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Affiliation(s)
- Sonal Agrawal
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82070, United States
| | - Julia Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82070, United States
| | | | - Jonathan H Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82070, United States.
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Berggren K, Agrawal S, Fox JA, Hildenbrand J, Nelson R, Bush AI, Fox JH. Amyloid Precursor Protein Haploinsufficiency Preferentially Mediates Brain Iron Accumulation in Mice Transgenic for The Huntington's Disease Mutation. J Huntingtons Dis 2018; 6:115-125. [PMID: 28550267 DOI: 10.3233/jhd-170242] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Huntington's disease (HD) is an autosomal dominant disorder caused by a CAG expansion in the huntingtin gene that results in expression of mutant huntingtin protein. Iron accumulates in HD brain neurons. Amyloid precursor protein (APP) promotes neuronal iron export. However, the role of APP in brain iron accumulation in HD is unclear. OBJECTIVE To determine the effects of APP insufficiency on HD in YAC128 mice. METHODS We crossed APP hemizygous mice (APP+/-) with YAC128 mice that are transgenic (Tg) for human mutant huntingtin (hmHTT) to generate APP+/+ hmHTT-/-, APP+/- hmHTT-/-, APP+/+ hmHTT+/- and APP+/- hmHTT+/- progeny. Mice were evaluated for behavioral, biochemical and neuropathology HD outcomes at 2-12 months of age. RESULTS APP heterozygosity decreased cortical APP 25% and 60% in non-Tg and Tg mice, respectively. Cerebral and striatal iron levels were increased by APP knockdown in Tg mice only. Nest-building behavior was decreased in Tg mice; APP knockdown decreased nest building in non-Tg but not Tg mice. Rota-rod endurance was decreased in Tg mice. APP+/- hHTT+/- mice demonstrated additional decreases in rota-rod endurance from 4-10 months of age. Tg mice had smaller striatal volumes and fewer striatal neurons but were not affected by APP knockdown. CONCLUSIONS APP heterozygosity results in greater decreases of cortical APP in Tg versus non-Tg mice. Mutant huntingtin transgenic mice develop brain iron accumulation as a result of greater suppression of APP levels. Elevated brain iron in Tg mice was associated with a decline in motor endurance consistent with a disease promoting effect of iron in the YAC128 model of human HD.
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Affiliation(s)
- Kiersten Berggren
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY, USA
| | - Sonal Agrawal
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY, USA
| | - Julia A Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY, USA
| | - Justin Hildenbrand
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY, USA
| | - Ryan Nelson
- Department of Zoology-Physiology, University of Wyoming, Laramie, WY, USA
| | - Ashley I Bush
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Australia
| | - Jonathan H Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY, USA
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Mouse models of neurodegenerative disease: preclinical imaging and neurovascular component. Brain Imaging Behav 2017; 12:1160-1196. [PMID: 29075922 DOI: 10.1007/s11682-017-9770-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Neurodegenerative diseases represent great challenges for basic science and clinical medicine because of their prevalence, pathologies, lack of mechanism-based treatments, and impacts on individuals. Translational research might contribute to the study of neurodegenerative diseases. The mouse has become a key model for studying disease mechanisms that might recapitulate in part some aspects of the corresponding human diseases. Neurodegenerative disorders are very complicated and multifactorial. This has to be taken in account when testing drugs. Most of the drugs screening in mice are very difficult to be interpretated and often useless. Mouse models could be condiderated a 'pathway models', rather than as models for the whole complicated construct that makes a human disease. Non-invasive in vivo imaging in mice has gained increasing interest in preclinical research in the last years thanks to the availability of high-resolution single-photon emission computed tomography (SPECT), positron emission tomography (PET), high field Magnetic resonance, Optical Imaging scanners and of highly specific contrast agents. Behavioral test are useful tool to characterize different animal models of neurodegenerative pathology. Furthermore, many authors have observed vascular pathological features associated to the different neurodegenerative disorders. Aim of this review is to focus on the different existing animal models of neurodegenerative disorders, describe behavioral tests and preclinical imaging techniques used for diagnose and describe the vascular pathological features associated to these diseases.
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Are Astrocytes the Predominant Cell Type for Activation of Nrf2 in Aging and Neurodegeneration? Antioxidants (Basel) 2017; 6:antiox6030065. [PMID: 28820437 PMCID: PMC5618093 DOI: 10.3390/antiox6030065] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 08/11/2017] [Accepted: 08/16/2017] [Indexed: 12/29/2022] Open
Abstract
Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that regulates hundreds of antioxidant genes, and is activated in response to oxidative stress. Given that many neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, Huntington’s disease and multiple sclerosis are characterised by oxidative stress, Nrf2 is commonly activated in these diseases. Evidence demonstrates that Nrf2 activity is repressed in neurons in vitro, and only cultured astrocytes respond strongly to Nrf2 inducers, leading to the interpretation that Nrf2 signalling is largely restricted to astrocytes. However, Nrf2 activity can be observed in neurons in post-mortem brain tissue and animal models of disease. Thus this interpretation may be false, and a detailed analysis of the cell type expression of Nrf2 in neurodegenerative diseases is required. This review describes the evidence for Nrf2 activation in each cell type in prominent neurodegenerative diseases and normal aging in human brain and animal models of neurodegeneration, the response to pharmacological and genetic modulation of Nrf2, and clinical trials involving Nrf2-modifying drugs.
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Agrawal S, Berggren KL, Marks E, Fox JH. Impact of high iron intake on cognition and neurodegeneration in humans and in animal models: a systematic review. Nutr Rev 2017; 75:456-470. [PMID: 28505363 PMCID: PMC5914328 DOI: 10.1093/nutrit/nux015] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Context Accumulation of brain iron is linked to aging and protein-misfolding neurodegenerative diseases. High iron intake may influence important brain health outcomes in later life. Objective The aim of this systematic review was to examine evidence from animal and human studies of the effects of high iron intake or peripheral iron status on adult cognition, brain aging, and neurodegeneration. Data Sources MEDLINE, Scopus, CAB Abstracts, the Cochrane Central Register of Clinical Trials, and OpenGrey databases were searched. Study Selection Studies investigating the effect of elevated iron intake at all postnatal life stages in mammalian models and humans on measures of adult brain health were included. Data Extraction Data were extracted and evaluated by two authors independently, with discrepancies resolved by discussion. Neurodegenerative disease diagnosis and/or behavioral/cognitive, biochemical, and brain morphologic findings were used to study the effects of iron intake or peripheral iron status on brain health. Risk of bias was assessed for animal and human studies. PRISMA guidelines for reporting systematic reviews were followed. Results Thirty-four preclinical and 14 clinical studies were identified from database searches. Thirty-three preclinical studies provided evidence supporting an adverse effect of nutritionally relevant high iron intake in neonates on brain-health-related outcomes in adults. Human studies varied considerably in design, quality, and findings; none investigated the effects of high iron intake in neonates/infants. Conclusions Human studies are needed to verify whether dietary iron intake levels used in neonates/infants to prevent iron deficiency have effects on brain aging and neurodegenerative disease outcomes.
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Affiliation(s)
- Sonal Agrawal
- S. Agrawal and J.H. Fox are with the Department of Veterinary Sciences, University of Wyoming, Laramie, Wyoming, USA. K.L. Berggren is with the Department of Radiation Oncology, University of New Mexico Cancer Center, Albuquerque, New Mexico, USA. E. Marks is with the Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Kiersten L. Berggren
- S. Agrawal and J.H. Fox are with the Department of Veterinary Sciences, University of Wyoming, Laramie, Wyoming, USA. K.L. Berggren is with the Department of Radiation Oncology, University of New Mexico Cancer Center, Albuquerque, New Mexico, USA. E. Marks is with the Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Eileen Marks
- S. Agrawal and J.H. Fox are with the Department of Veterinary Sciences, University of Wyoming, Laramie, Wyoming, USA. K.L. Berggren is with the Department of Radiation Oncology, University of New Mexico Cancer Center, Albuquerque, New Mexico, USA. E. Marks is with the Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Jonathan H. Fox
- S. Agrawal and J.H. Fox are with the Department of Veterinary Sciences, University of Wyoming, Laramie, Wyoming, USA. K.L. Berggren is with the Department of Radiation Oncology, University of New Mexico Cancer Center, Albuquerque, New Mexico, USA. E. Marks is with the Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
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