1
|
Sandri BJ, Kim J, Lubach GR, Lock EF, Ennis-Czerniak K, Kling PJ, Georgieff MK, Coe CL, Rao RB. Prognostic Performance of Hematological and Serum Iron and Metabolite Indices for Detection of Early Iron Deficiency Induced Metabolic Brain Dysfunction in Infant Rhesus Monkeys. J Nutr 2024; 154:875-885. [PMID: 38072152 PMCID: PMC10942850 DOI: 10.1016/j.tjnut.2023.10.031] [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: 08/11/2023] [Revised: 10/18/2023] [Accepted: 10/25/2023] [Indexed: 12/27/2023] Open
Abstract
BACKGROUND The current pediatric practice of monitoring for infantile iron deficiency (ID) via hemoglobin (Hgb) screening at one y of age does not identify preanemic ID nor protect against later neurocognitive deficits. OBJECTIVES To identify biomarkers of iron-related metabolic alterations in the serum and brain and determine the sensitivity of conventional iron and heme indices for predicting risk of brain metabolic dysfunction using a nonhuman primate model of infantile ID. METHODS Simultaneous serum iron and RBC indices, and serum and cerebrospinal fluid (CSF) metabolomic profiles were determined in 20 rhesus infants, comparing iron sufficient (IS; N = 10) and ID (N = 10) infants at 2 and 4 mo of age. RESULTS Reticulocyte hemoglobin (RET-He) was lower at 2 wk in the ID group. Significant IS compared with ID differences in serum iron indices were present at 2 mo, but Hgb and RBC indices differed only at 4 mo (P < 0.05). Serum and CSF metabolomic profiles of the ID and IS groups differed at 2 and 4 mo (P < 0.05). Key metabolites, including homostachydrine and stachydrine (4-5-fold lower at 4 mo in ID group, P < 0.05), were altered in both serum and CSF. Iron indices and RET-He at 2 mo, but not Hgb or other RBC indices, were correlated with altered CSF metabolic profile at 4 mo and had comparable predictive accuracy (area under the receiver operating characteristic curve scores, 0.75-0.80). CONCLUSIONS Preanemic ID at 2 mo was associated with metabolic alterations in serum and CSF in infant monkeys. Among the RBC indices, only RET-He predicted the future risk of abnormal CSF metabolic profile with a predictive accuracy comparable to serum iron indices. The concordance of homostachydrine and stachydrine changes in serum and CSF indicates their potential use as early biomarkers of brain metabolic dysfunction in infantile ID.
Collapse
Affiliation(s)
- Brian J Sandri
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States; Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, MN, United States
| | - Jonathan Kim
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States
| | - Gabriele R Lubach
- Harlow Center for Biological Psychology, University of Wisconsin, Madison, WI, United States
| | - Eric F Lock
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States
| | - Kathleen Ennis-Czerniak
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States
| | - Pamela J Kling
- Division of Neonatology, Department of Pediatrics, University of Wisconsin, Madison, WI, United States
| | - Michael K Georgieff
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States; Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, MN, United States
| | - Christopher L Coe
- Harlow Center for Biological Psychology, University of Wisconsin, Madison, WI, United States
| | - Raghavendra B Rao
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States; Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, MN, United States.
| |
Collapse
|
2
|
Huynh U, Zastrow ML. Metallobiology of Lactobacillaceae in the gut microbiome. J Inorg Biochem 2023; 238:112023. [PMID: 36270041 PMCID: PMC9888405 DOI: 10.1016/j.jinorgbio.2022.112023] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 09/26/2022] [Accepted: 10/03/2022] [Indexed: 11/21/2022]
Abstract
Lactobacillaceae are a diverse family of lactic acid bacteria found in the gut microbiota of humans and many animals. These bacteria exhibit beneficial effects on intestinal health, including modulating the immune system and providing protection against pathogens, and many species are frequently used as probiotics. Gut bacteria acquire essential metal ions, like iron, zinc, and manganese, through the host diet and changes to the levels of these metals are often linked to alterations in microbial community composition, susceptibility to infection, and gastrointestinal diseases. Lactobacillaceae are frequently among the organisms increased or decreased in abundance due to changes in metal availability, yet many of the molecular mechanisms underlying these changes have yet to be defined. Metal requirements and metallotransporters have been studied in some species of Lactobacillaceae, but few of the mechanisms used by these bacteria to respond to metal limitation or excess have been investigated. This review provides a current overview of these mechanisms and covers how iron, zinc, and manganese impact Lactobacillaceae in the gut microbiota with an emphasis on their biochemical roles, requirements, and homeostatic mechanisms in several species.
Collapse
Affiliation(s)
- Uyen Huynh
- Department of Chemistry, University of Houston, Houston, TX, USA
| | | |
Collapse
|
3
|
Balashova EA, Shadrina IL, Pogodina AA. Gastrointestinal side effects of iron supplements: potential effects on gut microbiota. ROSSIYSKIY VESTNIK PERINATOLOGII I PEDIATRII (RUSSIAN BULLETIN OF PERINATOLOGY AND PEDIATRICS) 2022. [DOI: 10.21508/1027-4065-2022-67-5-18-26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Iron deficiency anemia remains a significant problem in pediatric practice with its prevalence of 6–40% in the Russian Federation. Oral iron supplementation is the most common first-line treatment especially in outpatient setting. Despite adequate efficacy of oral supplementation, the problem of its side effects and, primarily, gastrointestinal toxicity remains. This review examines the issue of the potential effect of iron supplementation on gut microbiota composition, presents data from studies in animal models and in clinical studies.
Collapse
Affiliation(s)
| | - I. L. Shadrina
- Samara State Medical University;
Samara City Hospital No. 7
| | | |
Collapse
|
4
|
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.
Collapse
Affiliation(s)
| | | | | | | | - Bo Lönnerdal
- Department of Nutrition, University of California, Davis, CA 95616, USA
| |
Collapse
|
5
|
Abbas M, Hayirli Z, Drakesmith H, Andrews SC, Lewis MC. Effects of iron deficiency and iron supplementation at the host-microbiota interface: Could a piglet model unravel complexities of the underlying mechanisms? Front Nutr 2022; 9:927754. [PMID: 36267902 PMCID: PMC9577221 DOI: 10.3389/fnut.2022.927754] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 08/05/2022] [Indexed: 01/14/2023] Open
Abstract
Iron deficiency is the most prevalent human micronutrient deficiency, disrupting the physiological development of millions of infants and children. Oral iron supplementation is used to address iron-deficiency anemia and reduce associated stunting but can promote infection risk since restriction of iron availability serves as an innate immune mechanism against invading pathogens. Raised iron availability is associated with an increase in enteric pathogens, especially Enterobacteriaceae species, accompanied by reductions in beneficial bacteria such as Bifidobacteria and lactobacilli and may skew the pattern of gut microbiota development. Since the gut microbiota is the primary driver of immune development, deviations from normal patterns of bacterial succession in early life can have long-term implications for immune functionality. There is a paucity of knowledge regarding how both iron deficiency and luminal iron availability affect gut microbiota development, or the subsequent impact on immunity, which are likely to be contributors to the increased risk of infection. Piglets are naturally iron deficient. This is largely due to their low iron endowments at birth (primarily due to large litter sizes), and their rapid growth combined with the low iron levels in sow milk. Thus, piglets consistently become iron deficient within days of birth which rapidly progresses to anemia in the absence of iron supplementation. Moreover, like humans, pigs are omnivorous and share many characteristics of human gut physiology, microbiota and immunity. In addition, their precocial nature permits early maternal separation, individual housing, and tight control of nutritional intake. Here, we highlight the advantages of piglets as valuable and highly relevant models for human infants in promoting understanding of how early iron status impacts physiological development. We also indicate how piglets offer potential to unravel the complexities of microbiota-immune responses during iron deficiency and in response to iron supplementation, and the link between these and increased risk of infectious disease.
Collapse
Affiliation(s)
- Munawar Abbas
- Food and Nutritional Sciences, University of Reading, Reading, United Kingdom
| | - Zeynep Hayirli
- Food and Nutritional Sciences, University of Reading, Reading, United Kingdom
| | - Hal Drakesmith
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Simon C. Andrews
- School of Biological Sciences, University of Reading, Reading, United Kingdom
| | - Marie C. Lewis
- Food and Nutritional Sciences, University of Reading, Reading, United Kingdom
| |
Collapse
|
6
|
Trace Element Interactions, Inflammatory Signaling, and Male Sex Implicated in Reduced Growth Following Excess Oral Iron Supplementation in Pre-Weanling Rats. Nutrients 2022; 14:nu14193913. [PMID: 36235565 PMCID: PMC9571796 DOI: 10.3390/nu14193913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 09/16/2022] [Accepted: 09/20/2022] [Indexed: 11/17/2022] Open
Abstract
Iron supplements are frequently provided to infants in high-income countries despite low incidence of iron deficiency. There is growing concern regarding adverse health and development outcomes of excess iron provision in early life. Excess iron may directly damage developing organs through the formation of reactive oxygen species, alter systemic inflammatory signaling, and/or dysregulate trace mineral metabolism. To better characterize the in vivo effects of excess iron on development, we utilized a pre-weanling rat pup model. Lewis rat litters were culled to eight pups (four males and four females) and randomly assigned to daily supplementation groups receiving either vehicle control (CON; 10% w/v sucrose solution) or ferrous sulfate (FS) iron at one of the following doses: 10, 30, or 90 mg iron/kg body weight—FS-10, FS-30, and FS-90, respectively—from postnatal day (PD) 2 through 9. FS-90 litters, but not FS-30 or FS-10, failed to thrive compared to CON litters and had smaller brains on PD 10. Among the groups, FS-90 liver iron levels were highest, as were white blood cell counts. Compared to CON, circulating MCP-1 and liver zinc were increased in FS-90 pups, whereas liver copper was decreased. Growth defects due to excess FS provision in pre-weanling rats may be related to liver injury, inflammation, and altered trace mineral metabolism.
Collapse
|
7
|
Xu S, Ma L, Li H, Wang X, Wu M, Jing J, Chen X, Lan R, Tang W, Zhu Y. Iron Supplementation Is Associated with Improvement of Motor Development, Hemoglobin Level, and Weight in Preterm Infants during the First Year of Life in China. Nutrients 2022; 14:nu14132624. [PMID: 35807810 PMCID: PMC9267941 DOI: 10.3390/nu14132624] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/18/2022] [Accepted: 06/19/2022] [Indexed: 01/27/2023] Open
Abstract
Iron supplementation is recommended for preterm infants due to impaired iron endowment. However, the health outcomes of this recommendation remain controversial. Thus, this study aimed to determine the association of iron supplementation with neurobehavioral development, hemoglobin (Hb), and anthropometric characteristics in preterm infants. A retrospective cohort design was applied to collect data from 1568 preterm infants at 0–3 months of corrected age (mo CA) from a hospital in South China. Infants were categorized into a 3-month iron supplementation group (IG, n = 697) or a control group (CG, n = 871) according to medical records, and then followed through to 12 mo CA. Data on neurobehavioral development, anthropometry, Hb level, history of diseases, and nutrition were collected at 3, 6, and 12 mo CA. The results showed that, compared with the CG, iron supplementation was positively related to improved gross motor skills and weight at 6 mo CA (β = 1.894, β = 5.322) and 12 mo CA (β = 4.019, β = 6.830) and fine motor skills at 12 mo CA (β = 1.980), after adjustment for confounding factors including illness, nutritional supplements, and diet. Iron supplementation was also related to elevated Hb levels and its increase at 3 mo CA (β = 2.196, β = 3.920) and 6 mo CA (β = 3.011, β = 7.259). In conclusion, iron supplementation for 3 months in Chinese preterm infants is positively associated with improved motor development, elevated Hb levels, and higher body weight during the first year of life.
Collapse
Affiliation(s)
- Suhua Xu
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
| | - Liya Ma
- Shenzhen Bao’an Women and Children’s Hospital, Jinan University, Shenzhen 518102, China;
| | - Hailin Li
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
| | - Xiaotong Wang
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
| | - Miao Wu
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
| | - Jiajia Jing
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
| | - Xiaoyan Chen
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
| | - Ruiling Lan
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
| | - Weike Tang
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
| | - Yanna Zhu
- Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China; (S.X.); (H.L.); (X.W.); (M.W.); (J.J.); (X.C.); (R.L.); (W.T.)
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
- Correspondence: ; Tel.: +86-20-87334627; Fax: +86-20-87330446
| |
Collapse
|
8
|
Reply. J Pediatr 2022; 243:238-239. [PMID: 35041810 DOI: 10.1016/j.jpeds.2022.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 01/12/2022] [Indexed: 11/21/2022]
|
9
|
Ribeiro M, Fonseca L, Anjos JS, Capo-Chichi JCC, Borges NA, Burrowes J, Mafra D. Oral iron supplementation in patients with chronic kidney disease: Can it be harmful to the gut microbiota? Nutr Clin Pract 2021; 37:81-93. [PMID: 33979013 DOI: 10.1002/ncp.10662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Patients with chronic kidney disease (CKD) have several pathophysiological alterations, including anemia, one of the first changes in CKD patients. More recently, researchers have observed that the intestinal microbiota alterations are also another complication in these patients. The most common treatment for anemia is oral (mainly ferrous sulfate) or intravenous iron supplementation. Despite being a necessary treatment, recent studies have reported that supplementation with oral iron may increase its availability in the intestine, leading to disturbance in the gut microbiota and also to oxidative stress in the enterocytes, which may change the permeability and the microbiota profile. Although it is a therapy routinely used in patients with CKD, supplementation with oral iron on the gut microbiota has been rarely studied in these patients. Thus, this review will discuss the relationship between iron and the gut microbiota and the possible effects of oral iron supplementation on gut microbiota in patients with CKD.
Collapse
Affiliation(s)
- Marcia Ribeiro
- Graduate Program in Nutrition Sciences, Fluminense Federal University (UFF), Niterói, Rio de Janeiro, Brazil.,Unidade de Pesquisa Clinica (UPC)-University Hospital Antonio Pedro, Niterói, Rio de Janeiro, Brazil
| | - Larissa Fonseca
- Unidade de Pesquisa Clinica (UPC)-University Hospital Antonio Pedro, Niterói, Rio de Janeiro, Brazil.,Graduate Program in Medical Sciences, Fluminense Federal University (UFF), Niterói, Rio de Janeiro, Brazil
| | - Juliana S Anjos
- Unidade de Pesquisa Clinica (UPC)-University Hospital Antonio Pedro, Niterói, Rio de Janeiro, Brazil.,Graduate Program in Cardiovascular Sciences, Fluminense Federal University (UFF), Niterói, Rio de Janeiro, Brazil
| | - Jean C C Capo-Chichi
- Graduate Program in Medical Sciences, Fluminense Federal University (UFF), Niterói, Rio de Janeiro, Brazil
| | - Natália A Borges
- Institute of Nutrition, Rio de Janeiro State University (UERJ), Rio de Janeiro, RJ, Brazil
| | | | - Denise Mafra
- Graduate Program in Nutrition Sciences, Fluminense Federal University (UFF), Niterói, Rio de Janeiro, Brazil.,Unidade de Pesquisa Clinica (UPC)-University Hospital Antonio Pedro, Niterói, Rio de Janeiro, Brazil.,Graduate Program in Cardiovascular Sciences, Fluminense Federal University (UFF), Niterói, Rio de Janeiro, Brazil.,Graduate Program in Medical Sciences, Fluminense Federal University (UFF), Niterói, Rio de Janeiro, Brazil
| |
Collapse
|
10
|
Jahan S, Bisrat F, Faruque MO, Ferdaus MJ, Khan SS, Farzana T. Formulation of nutrient enriched germinated wheat and mung-bean based weaning food compare to locally available similar products in Bangladesh. Heliyon 2021; 7:e06974. [PMID: 34027177 PMCID: PMC8120945 DOI: 10.1016/j.heliyon.2021.e06974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 03/17/2021] [Accepted: 04/27/2021] [Indexed: 11/02/2022] Open
Abstract
Poor weaning practice and malnutrition among under 5 (yrs) children are still major public health issues in Bangladesh. This study aimed to develop a cheap and nutritious weaning food for the children of Bangladesh. For this purpose, three weaning formulations of Q1, Q2, and Q3 with different ratios of germinated wheat, germinated mung-bean, and soya-bean, and a constant amount of sweet potato, sugar, salt, and milk flavor were processed and evaluated. The prepared formulations were investigated for proximate composition and sensory evaluation and compared with six commercial weaning food products. The proximate composition values indicated that the fat content of formulated foods ranged between 09.29% and 11.40%. The carbohydrate content was ranged between 52.80% and 61.20%, which was low compared with commercial ones. The protein content of the formulated foods was 20.33%-27.70%, and that was approximately two times more than available commercial foods. The energy content was also more than locally available commercial weaning foods, which were 411.40 ± 1.51 kcal to 419.30 ± 1.12 kcal. Sample Q2 had an 8.4 acceptance score in sensory analysis of a 9-point hedonic scale scorecard, which made it more acceptable than the other two samples. The values of mineral elements (Na, K, Fe) were similar to all analyzed varieties of commercial weaning foods. This nutrient-enriched weaning food will easily be affordable for the people of developing countries like Bangladesh. The results showed that the formulated weaning food had the desired characteristics of a weaning food; hence, it could decrease malnutrition in children.
Collapse
Affiliation(s)
- Sharmin Jahan
- Department of Food and Nutrition, College of Home Economics, University of Dhaka, Dhaka 1205, Bangladesh
| | - Fahiza Bisrat
- Institute of Food Science and Technology, Bangladesh Council of Scientific and Industrial Research, Dhaka 1205, Bangladesh
| | - M Omar Faruque
- Department of Nutrition and Food Technology, Jashore University of Science and Technology, Jashore 7408, Bangladesh
| | - Md Jannatul Ferdaus
- Department of Nutrition and Food Technology, Jashore University of Science and Technology, Jashore 7408, Bangladesh
| | - Shompa Sharmin Khan
- Department of Food and Nutrition, College of Home Economics, University of Dhaka, Dhaka 1205, Bangladesh
| | - Tasnim Farzana
- Institute of Food Science and Technology, Bangladesh Council of Scientific and Industrial Research, Dhaka 1205, Bangladesh
| |
Collapse
|
11
|
Botta A, Barra NG, Lam NH, Chow S, Pantopoulos K, Schertzer JD, Sweeney G. Iron Reshapes the Gut Microbiome and Host Metabolism. J Lipid Atheroscler 2021; 10:160-183. [PMID: 34095010 PMCID: PMC8159756 DOI: 10.12997/jla.2021.10.2.160] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 02/12/2021] [Accepted: 02/21/2021] [Indexed: 12/12/2022] Open
Abstract
Compelling studies have established that the gut microbiome is a modifier of metabolic health. Changes in the composition of the gut microbiome are influenced by genetics and the environment, including diet. Iron is a potential node of crosstalk between the host-microbe relationship and metabolic disease. Although iron is well characterized as a frequent traveling companion of metabolic disease, the role of iron is underappreciated because the mechanisms of iron's influence on host metabolism are poorly characterized. Both iron deficiency and excessive amounts leading to iron overload can have detrimental effects on cardiometabolic health. Optimal iron homeostasis is critical for regulation of host immunity and metabolism in addition to regulation of commensal and pathogenic enteric bacteria. In this article we review evidence to support the notion that altering composition of the gut microbiome may be an important route via which iron impacts cardiometabolic health. We discuss reshaping of the microbiome by iron, the physiological significance and the potential for therapeutic interventions.
Collapse
Affiliation(s)
- Amy Botta
- Department of Biology, York University, Toronto, ON, Canada
| | - Nicole G. Barra
- Department of Biochemistry and Biomedical Sciences, Farncombe Family Digestive Health Research Institute, Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON, Canada
| | - Nhat Hung Lam
- Department of Biology, York University, Toronto, ON, Canada
| | - Samantha Chow
- Department of Biology, York University, Toronto, ON, Canada
| | - Kostas Pantopoulos
- Lady Davis Institute for Medical Research, Jewish General Hospital and Department of Medicine, McGill University, Montreal, QC, Canada
| | - Jonathan D. Schertzer
- Department of Biochemistry and Biomedical Sciences, Farncombe Family Digestive Health Research Institute, Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, ON, Canada
| | - Gary Sweeney
- Department of Biology, York University, Toronto, ON, Canada
| |
Collapse
|
12
|
McMillen S, Lönnerdal B. Postnatal Iron Supplementation with Ferrous Sulfate vs. Ferrous Bis-Glycinate Chelate: Effects on Iron Metabolism, Growth, and Central Nervous System Development in Sprague Dawley Rat Pups. Nutrients 2021; 13:1406. [PMID: 33921980 PMCID: PMC8143548 DOI: 10.3390/nu13051406] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/18/2021] [Accepted: 04/20/2021] [Indexed: 02/05/2023] Open
Abstract
Iron-fortified formulas and iron drops (both usually ferrous sulfate, FS) prevent early life iron deficiency, but may delay growth and adversely affect neurodevelopment by providing excess iron. We used a rat pup model to investigate iron status, growth, and development outcomes following daily iron supplementation (10 mg iron/kg body weight, representative of iron-fortified formula levels) with FS or an alternative, bioavailable form of iron, ferrous bis-glycinate chelate (FC). On postnatal day (PD) 2, sex-matched rat litters (n = 3 litters, 10 pups each) were randomly assigned to receive FS, FC, or vehicle control until PD 14. On PD 15, we evaluated systemic iron regulation and CNS mineral interactions and we interrogated iron loading outcomes in the hippocampus, in search of mechanisms by which iron may influence neurodevelopment. Body iron stores were elevated substantially in iron-supplemented pups. All pups gained weight normally, but brain size on PD 15 was dependent on iron source. This may have been associated with reduced hippocampal oxidative stress but was not associated with CNS mineral interactions, iron regulation, or myelination, as these were unchanged with iron supplementation. Additional studies are warranted to investigate iron form effects on neurodevelopment so that iron recommendations can be optimized for all infants.
Collapse
Affiliation(s)
| | - Bo Lönnerdal
- Department of Nutrition, University of California, Davis, CA 95616, USA;
| |
Collapse
|
13
|
Sandri BJ, Lubach GR, Lock EF, Kling PJ, Georgieff MK, Coe CL, Rao RB. Correcting iron deficiency anemia with iron dextran alters the serum metabolomic profile of the infant Rhesus Monkey. Am J Clin Nutr 2021; 113:915-923. [PMID: 33740040 PMCID: PMC8023818 DOI: 10.1093/ajcn/nqaa393] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 11/24/2020] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND The effects of infantile iron deficiency anemia (IDA) extend beyond hematological indices and include short- and long-term adverse effects on multiple cells and tissues. IDA is associated with an abnormal serum metabolomic profile, characterized by altered hepatic metabolism, lowered NAD flux, increased nucleoside levels, and a reduction in circulating dopamine levels. OBJECTIVES The objective of this study was to determine whether the serum metabolomic profile is normalized after rapid correction of IDA using iron dextran injections. METHODS Blood was collected from iron-sufficient (IS; n = 10) and IDA (n = 12) rhesus infants at 6 months of age. IDA infants were then administered iron dextran and vitamin B via intramuscular injections at weekly intervals for 2 to 8 weeks. Their hematological and metabolomic statuses were evaluated following treatment and compared with baseline and a separate group of age-matched IS infants (n = 5). RESULTS Serum metabolomic profiles assessed at baseline and after treatment via HPLC/MS using isobaric standards identified 654 quantifiable metabolites. At baseline, 53 metabolites differed between IS and IDA infants. Iron treatment restored traditional hematological indices, including hemoglobin and mean corpuscular volume, into the normal range, but the metabolite profile in the IDA group after iron treatment was markedly altered, with 323 metabolites differentially expressed when compared with an infant's own baseline profile. CONCLUSIONS Rapid correction of IDA with iron dextran resulted in extensive metabolic changes across biochemical pathways indexing the liver function, bile acid release, essential fatty acid production, nucleoside release, and several neurologically important metabolites. The results highlight the importance of a cautious approach when developing a route and regimen of iron repletion to treat infantile IDA.
Collapse
Affiliation(s)
- Brian J Sandri
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, MN, USA,Center for Neurobehavioral Development, University of Minnesota, Minneapolis, MN, USA
| | - Gabriele R Lubach
- Harlow Center for Biological Psychology, University of Wisconsin, Madison, WI, USA
| | - Eric F Lock
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, USA
| | - Pamela J Kling
- Division of Neonatology, Department of Pediatrics, University of Wisconsin, Madison, WI, USA
| | - Michael K Georgieff
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, MN, USA,Center for Neurobehavioral Development, University of Minnesota, Minneapolis, MN, USA
| | - Christopher L Coe
- Harlow Center for Biological Psychology, University of Wisconsin, Madison, WI, USA
| | | |
Collapse
|
14
|
Seyoum Y, Baye K, Humblot C. Iron homeostasis in host and gut bacteria - a complex interrelationship. Gut Microbes 2021; 13:1-19. [PMID: 33541211 PMCID: PMC7872071 DOI: 10.1080/19490976.2021.1874855] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 12/16/2020] [Accepted: 01/03/2021] [Indexed: 02/08/2023] Open
Abstract
Iron deficiency is the most frequent nutritional deficiency in the world with an estimated 1.4 billion people affected. The usual way to fight iron deficiency is iron fortification, but this approach is not always effective and can have undesirable side effects including an increase in the growth and virulence of gut bacterial pathogens responsible for diarrhea and gut inflammation. Iron is mainly absorbed in the duodenum and is tightly regulated in mammals. Unabsorbed iron enters the colonic lumen where many microorganisms, referred to as gut microbiota, reside. Iron is essential for these bacteria, and its availability consequently affects this microbial ecosystem. The aim of this review is to provide further insights into the complex relationship between iron and gut microbiota. Given that overcoming anemia caused by iron deficiency is still a challenge today, gut microbiota could help identify more efficient ways to tackle this public health problem.
Collapse
Affiliation(s)
- Yohannes Seyoum
- Center for Food Science and Nutrition, College of Natural and Computational Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Kaleab Baye
- Center for Food Science and Nutrition, College of Natural and Computational Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Christèle Humblot
- QualiSud, Université de Montpellier, Avignon Université, CIRAD, Institut Agro, IRD, Université de la Réunion, Montpellier, France
| |
Collapse
|
15
|
Abstract
Iron supplementation and fortification are used to treat iron deficiency, which is often associated with gastrointestinal conditions, such as inflammatory bowel disease and colorectal cancer. Within the gut, commensal bacteria contribute to maintaining systemic iron homeostasis. Disturbances that lead to excess iron promote the replication and virulence of enteric pathogens. Consequently, research has been interested in better understanding the effects of iron supplementation and fortification on gut bacterial composition and overall gut health. While animal and human trials have shown seemingly conflicting results, these studies emphasize how numerous factors influence gut microbial composition. Understanding how different iron formulations and doses impact specific bacteria will improve the outcomes of iron supplementation and fortification in humans. Furthermore, discerning the nuances of iron supplementation and fortification will benefit subpopulations that currently do not respond well to treatment.
Collapse
|
16
|
Van Belkum M, Mendoza Alvarez L, Neu J. Preterm neonatal immunology at the intestinal interface. Cell Mol Life Sci 2020; 77:1209-1227. [PMID: 31576423 PMCID: PMC11105006 DOI: 10.1007/s00018-019-03316-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/21/2019] [Accepted: 09/19/2019] [Indexed: 12/17/2022]
Abstract
Fetal and neonatal development represents a critical window for setting a path toward health throughout life. In this review, we focus on intestinal immunity, how it develops, and its implications for subsequent neonatal diseases. We discuss maternal nutritional and environmental exposures that dictate outcomes for the developing fetus. Although still controversial, there is evidence in support of an in utero microbiome. Specific well-intentioned and routine applications of antibiotics, steroids, and surgical interventions implemented before, during, and after birth skew the neonate towards pro-inflammatory dysbiosis. Shortly after birth, a consortium of maternal and environmentally derived bacteria, through cross-talk with the developing host immune system, takes center stage in developing or disrupting immune homeostasis at the intestinal interface. We also examine subsequent immunological cross-talks, which involve neonatal myeloid and lymphoid responses, and their potential impacts on health and disease such as necrotizing enterocolitis and sepsis, especially critical disease entities for the infant born preterm.
Collapse
Affiliation(s)
- Max Van Belkum
- Division of Neonatology, Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Lybil Mendoza Alvarez
- Division of Neonatology, Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Josef Neu
- Division of Neonatology, Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
| |
Collapse
|
17
|
Ji P, B Nonnecke E, Doan N, Lönnerdal B, Tan B. Excess Iron Enhances Purine Catabolism Through Activation of Xanthine Oxidase and Impairs Myelination in the Hippocampus of Nursing Piglets. J Nutr 2019; 149:1911-1919. [PMID: 31373370 DOI: 10.1093/jn/nxz166] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/17/2019] [Accepted: 06/20/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Few studies have addressed the risk of nutritional iron overexposure in infancy. We previously found that excess dietary iron in nursing piglets resulted in iron overload in the liver and hippocampus and diminished socialization with novel conspecifics in a test for social novelty preference. OBJECTIVES This experiment aimed to identify metabolites and metabolic pathways affected by iron overload in the liver and hippocampus of nursing piglets. METHODS Liver and hippocampal tissues collected from 22-d-old piglets (Hampshire × Yorkshire crossbreed; 5.28 ± 0.53 kg body weight; 50% male) that received orally 0 (NI group) or 50 mg iron/(d · kg body weight) (HI group) from postnatal day (PD) 2 to PD21 were analyzed for mRNA and protein expression and enzyme activity of xanthine oxidase (XO). Untargeted metabolomics was performed using GC-MS. Expression of myelin basic protein (MBP) in the hippocampus was determined using western blot. RESULTS There were 108 and 126 metabolites identified in the hippocampus and liver, respectively. Compared with NI, HI altered 15 metabolites (P < 0.05, q < 0.2) in the hippocampus, including a reduction in myo-inositol (0.86-fold) and N-acetylaspartic acid (0.84-fold), 2 metabolites important for neuronal function and myelination. Seven metabolites involved in purine and pyrimidine metabolism (e.g., hypoxanthine, xanthine, and β-alanine) were coordinately changed in the hippocampus (P < 0.05, q < 0.2), suggesting that iron excess enhanced purine catabolism. The mRNA expression (2.3-fold) (P < 0.05) and activity of XO, a rate-limiting enzyme in purine degradation, was increased. Excess iron increased hippocampal lipid peroxidation by 74% (P < 0.05) and decreased MBP by 44% (P = 0.053). The hepatic metabolome was unaffected. CONCLUSIONS In nursing piglets, excess iron enhances hippocampal purine degradation through activation of XO, which may induce oxidative stress and alter energy metabolism in the developing brain.
Collapse
Affiliation(s)
- Peng Ji
- Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Eric B Nonnecke
- Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Nicole Doan
- Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Bo Lönnerdal
- Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Bie Tan
- Laboratory of Animal Nutritional Physiology and Metabolic Process, Key Laboratory of Agro-ecological Processes in Subtropical Region, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, China
| |
Collapse
|
18
|
Parmanand BA, Kellingray L, Le Gall G, Basit AW, Fairweather-Tait S, Narbad A. A decrease in iron availability to human gut microbiome reduces the growth of potentially pathogenic gut bacteria; an in vitro colonic fermentation study. J Nutr Biochem 2019; 67:20-27. [PMID: 30831460 PMCID: PMC6546957 DOI: 10.1016/j.jnutbio.2019.01.010] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 01/17/2019] [Accepted: 01/18/2019] [Indexed: 02/06/2023]
Abstract
Iron supplements are widely consumed; however most of the iron is not absorbed and enters the colon where potentially pathogenic bacteria can utilise it for growth. This study investigated the effect of iron availability on human gut microbial composition and function using an in vitro colonic fermentation model inoculated with faecal microbiota from healthy adult donors, as well as examining the effect of iron on the growth of individual gut bacteria. Batch fermenters were seeded with fresh faecal material and supplemented with the iron chelator, bathophenanthroline disulphonic acid (BPDS). Samples were analysed at regular intervals to assess impact on the gut bacterial communities. The growth of Escherichia coli and Salmonella typhimurium was significantly impaired when cultured independently in iron-deficient media. In contrast, depletion of iron did not affect the growth of the beneficial species, Lactobacillus rhamnosus, when cultured independently. Analysis of the microbiome composition via 16S-based metataxonomics indicated that under conditions of iron chelation, the relative abundance decreased for several taxa, including a 10% decrease in Escherichia and a 15% decrease in Bifidobacterium. Metabolomics analysis using 1 H-NMR indicated that the production of SCFAs was reduced under iron-limited conditions. These results support previous studies demonstrating the essentiality of iron for microbial growth and metabolism, but, in addition, they indicate that iron chelation changes the gut microbiota profile and influences human gut microbial homeostasis through both compositional and functional changes.
Collapse
Affiliation(s)
- Bhavika A Parmanand
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich, NR4 7UA, UK; Faculty of Medicine and Health, University of East Anglia, Norwich, NR4 7TJ, UK
| | - Lee Kellingray
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich, NR4 7UA, UK
| | - Gwenaelle Le Gall
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich, NR4 7UA, UK
| | - Abdul W Basit
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK; Intract Pharma, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | | | - Arjan Narbad
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich, NR4 7UA, UK
| |
Collapse
|
19
|
Volani C, Paglia G, Smarason SV, Pramstaller PP, Demetz E, Pfeifhofer-Obermair C, Weiss G. Metabolic Signature of Dietary Iron Overload in a Mouse Model. Cells 2018; 7:cells7120264. [PMID: 30544931 PMCID: PMC6315421 DOI: 10.3390/cells7120264] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/03/2018] [Accepted: 12/07/2018] [Indexed: 12/28/2022] Open
Abstract
Iron is an essential co-factor for several metabolic processes, including the Krebs cycle and mitochondrial oxidative phosphorylation. Therefore, maintaining an appropriate iron balance is essential to ensure sufficient energy production and to avoid excessive reactive oxygen species formation. Iron overload impairs mitochondrial fitness; however, little is known about the associated metabolic changes. Here we aimed to characterize the metabolic signature triggered by dietary iron overload over time in a mouse model, where mice received either a standard or a high-iron diet. Metabolic profiling was assessed in blood, plasma and liver tissue. Peripheral blood was collected by means of volumetric absorptive microsampling (VAMS). Extracted blood and tissue metabolites were analyzed by liquid chromatography combined to high resolution mass spectrometry. Upon dietary iron loading we found increased glucose, aspartic acid and 2-/3-hydroxybutyric acid levels but low lactate and malate levels in peripheral blood and plasma, pointing to a re-programming of glucose homeostasis and the Krebs cycle. Further, iron loading resulted in the stimulation of the urea cycle in the liver. In addition, oxidative stress was enhanced in circulation and coincided with increased liver glutathione and systemic cysteine synthesis. Overall, iron supplementation affected several central metabolic circuits over time. Hence, in vivo investigation of metabolic signatures represents a novel and useful tool for getting deeper insights into iron-dependent regulatory circuits and for monitoring of patients with primary and secondary iron overload, and those ones receiving iron supplementation therapy.
Collapse
Affiliation(s)
- Chiara Volani
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
- Christian Doppler Laboratory for Iron Metabolism and Anemia Research, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
- Institute for Biomedicine, Eurac Research, Via Galvani 31, 39100 Bolzano, Italy.
| | - Giuseppe Paglia
- Institute for Biomedicine, Eurac Research, Via Galvani 31, 39100 Bolzano, Italy.
| | - Sigurdur V Smarason
- Institute for Biomedicine, Eurac Research, Via Galvani 31, 39100 Bolzano, Italy.
| | - Peter P Pramstaller
- Institute for Biomedicine, Eurac Research, Via Galvani 31, 39100 Bolzano, Italy.
| | - Egon Demetz
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
| | - Christa Pfeifhofer-Obermair
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
| | - Guenter Weiss
- Department of Internal Medicine II, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
- Christian Doppler Laboratory for Iron Metabolism and Anemia Research, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
| |
Collapse
|
20
|
Nemkov T, Reisz JA, Xia Y, Zimring JC, D’Alessandro A. Red blood cells as an organ? How deep omics characterization of the most abundant cell in the human body highlights other systemic metabolic functions beyond oxygen transport. Expert Rev Proteomics 2018; 15:855-864. [DOI: 10.1080/14789450.2018.1531710] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Travis Nemkov
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver – Aurora, CO, USA
| | - Julie A. Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver – Aurora, CO, USA
| | - Yang Xia
- Department of Biochemistry, University of Texas Houston – McGovern Medical School , Houston, TX, USA
| | | | - Angelo D’Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver – Aurora, CO, USA
| |
Collapse
|
21
|
Lau WL, Vaziri ND, Nunes ACF, Comeau AM, Langille MGI, England W, Khazaeli M, Suematsu Y, Phan J, Whiteson K. The Phosphate Binder Ferric Citrate Alters the Gut Microbiome in Rats with Chronic Kidney Disease. J Pharmacol Exp Ther 2018; 367:452-460. [DOI: 10.1124/jpet.118.251389] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 09/28/2018] [Indexed: 01/04/2023] Open
|
22
|
Cussotto S, Sandhu KV, Dinan TG, Cryan JF. The Neuroendocrinology of the Microbiota-Gut-Brain Axis: A Behavioural Perspective. Front Neuroendocrinol 2018; 51:80-101. [PMID: 29753796 DOI: 10.1016/j.yfrne.2018.04.002] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 04/23/2018] [Accepted: 04/23/2018] [Indexed: 12/17/2022]
Abstract
The human gut harbours trillions of symbiotic bacteria that play a key role in programming different aspects of host physiology in health and disease. These intestinal microbes are also key components of the gut-brain axis, the bidirectional communication pathway between the gut and the central nervous system (CNS). In addition, the CNS is closely interconnected with the endocrine system to regulate many physiological processes. An expanding body of evidence is supporting the notion that gut microbiota modifications and/or manipulations may also play a crucial role in the manifestation of specific behavioural responses regulated by neuroendocrine pathways. In this review, we will focus on how the intestinal microorganisms interact with elements of the host neuroendocrine system to modify behaviours relevant to stress, eating behaviour, sexual behaviour, social behaviour, cognition and addiction.
Collapse
Affiliation(s)
- Sofia Cussotto
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Kiran V Sandhu
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland
| | - John F Cryan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland.
| |
Collapse
|
23
|
Lönnerdal B. Excess iron intake as a factor in growth, infections, and development of infants and young children. Am J Clin Nutr 2017; 106:1681S-1687S. [PMID: 29070544 PMCID: PMC5701711 DOI: 10.3945/ajcn.117.156042] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The provision of iron via supplementation or the fortification of foods has been shown to be effective in preventing and treating iron deficiency and iron deficiency anemia in infants and young children. However, iron is a pro-oxidative element and can have negative effects on biological systems even at moderate amounts. An increasing number of studies have reported adverse effects of iron that was given to infants and young-children populations who initially were iron replete. These effects include decreased growth (both linear growth and weight), increased illness (usually diarrhea), interactions with other trace elements such as copper and zinc, altered gut microbiota to more pathogenic bacteria, increased inflammatory markers, and impaired cognitive and motor development. If these results can be confirmed by larger and well-controlled studies, it may have considerable programmatic implications (e.g., the necessity to screen for iron status before interventions to exclude iron-replete individuals). A lack of understanding of the mechanisms underlying these adverse outcomes limits our ability to modify present supplementation and fortification strategies. This review summarizes studies on the adverse effects of iron on various outcomes; suggests possible mechanisms that may explain these observations, which are usually made in clinical studies and intervention trials; and gives examples from animal models and in vitro studies. With a better understanding of these mechanisms, it may be possible to find novel ways of providing iron in a form that causes fewer or no adverse effects even when subjects are iron replete. However, it is apparent that our understanding is limited, and research in this area is urgently needed.
Collapse
Affiliation(s)
- Bo Lönnerdal
- Department of Nutrition, University of California, Davis, Davis, CA
| |
Collapse
|