Oxidative stress is a common denominator in the pathogenesis of many chronic diseases. Therefore, antioxidants are often used to protect cells and tissues and reverse oxidative damage. It is well ...known that iron metabolism underlies the dynamic interplay between oxidative stress and antioxidants in many pathophysiological processes. Both iron deficiency and iron overload can affect redox state, and these conditions can be restored to physiological conditions using iron supplementation and iron chelation, respectively. Similarly, the addition of antioxidants to these treatment regimens has been suggested as a viable therapeutic approach for attenuating tissue damage induced by oxidative stress. Notably, many bioactive plant-derived compounds have been shown to regulate both iron metabolism and redox state, possibly through interactive mechanisms. This review summarizes our current understanding of these mechanisms and discusses compelling preclinical evidence that bioactive plant-derived compounds can be both safe and effective for managing both iron deficiency and iron overload conditions.
Prevalence of iron deficiency anemia and its related mortality rate are on the rise in the United States and causes are unclear.
The aim was to examine trends and causes of Fe deficiency anemia ...prevalence and Fe deficiency–related mortality rates in the total US population.
Changes in daily dietary Fe intake, serum iron concentration, hemoglobin, red cell distribution width (RDW), and mean corpuscular volume (MCV) obtained from the laboratory files of NHANES, Fe deficiency anemia–related mortality rates from the CDC, and iron concentrations of US food products from the USDA between 1999 and 2018 were analyzed.
Of food items with revised concentrations in USDA Nutrient Database for Standard Reference SR28 (2015), 62.4% had lower Fe concentrations than in SR11 (1999). There was a 15.3% reduction in beef (relatively higher in heme iron) and a 21.5% increase in chicken meat consumption in the American diet between 1999 and 2018. Dietary iron intake decreased by ∼6.6% and ∼9.5% for male and female adults, respectively. Increases of prevalence of estimated anemia in the United States ranged from 10.5% to 106% depending on age and sex. Age-adjusted mortality rates with iron deficiency anemia as the underlying cause of death increased from ∼0.04 to ∼0.08 deaths per 100,000 people, whereas all other anemias as the underlying causes of death decreased by ≥25%. Mean RDW and serum folate concentrations increased, whereas hemoglobin, serum iron concentrations, and MCV, parameters traditionally associated with Fe deficiency anemia, decreased during this period.
Increased iron deficiency anemia and related mortality rates in the US population between 1999 and 2018 were likely related to the decline in dietary iron intake resulting from an Fe concentration decline in US food products and a shift in dietary patterns.
Iron deficiency is the most prevalent nutritional deficiency affecting children and adolescents worldwide. A consistent body of epidemiological data demonstrates an increased incidence of iron ...deficiency at three timepoints: in the neonatal period, in preschool children, and in adolescents, where it particularly affects females.
Conclusion
: This narrative review focuses on the most suggestive symptoms of iron deficiency in childhood, describes the diagnostic procedures in situations with or without anemia, and provides Swiss expert-based management recommendations for the pediatric context.
What is Known:
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Iron deficiency (ID) is one of the most common challenges faced by pediatricians.
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Significant progress in the diagnosis and therapy of ID has been made over the last decade.
What is New:
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Our expert panel provides ID management recommendations based on the best available evidence.
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They include strategies for ID diagnosis and therapy, both oral and intravenous.
Ferroportin (FPN), the only known vertebrate iron exporter, transports iron from intestinal, splenic, and hepatic cells into the blood to provide iron to other tissues and cells in vivo. Most of the ...circulating iron is consumed by erythroid cells to synthesize hemoglobin. Here we found that erythroid cells not only consumed large amounts of iron, but also returned significant amounts of iron to the blood. Erythroblast-specific Fpn knockout (Fpn KO) mice developed lower serum iron levels in conjunction with tissue iron overload and increased FPN expression in spleen and liver without changing hepcidin levels. Our results also showed that Fpn KO mice, which suffer from mild hemolytic anemia, were sensitive to phenylhydrazine-induced oxidative stress but were able to tolerate iron deficiency upon exposure to a low-iron diet and phlebotomy, supporting that the anemia of Fpn KO mice resulted from erythrocytic iron overload and resulting oxidative injury rather than a red blood cell (RBC) production defect. Moreover, we found that the mean corpuscular volume (MCV) values of gain-of-function FPN mutation patients were positively associated with serum transferrin saturations, whereas MCVs of loss-of-function FPN mutation patients were not, supporting that erythroblasts donate iron to blood through FPN in response to serum iron levels. Our results indicate that FPN of erythroid cells plays an unexpectedly essential role in maintaining systemic iron homeostasis and protecting RBCs from oxidative stress, providing insight into the pathophysiology of FPN diseases.
•FPN on erythroid cells contributes a significant amount of iron to the blood.•FPN deficiency predisposes RBCs to oxidative injury.
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Iron‐meteorite groups that appear from published isotopic data to have been derived from melted carbonaceous‐chondrite‐like precursors (CC irons) (IIC, IID, IIF, IIIF, IVB) tend to have higher median ...refractory siderophile element (RSE) contents, higher median Ni contents, and higher median Ir/Ni and Ir/Au ratios than magmatic noncarbonaceous (NC) iron‐meteorite groups (IC, IIAB, IIIAB, IIIE, IVA). (Group IIG is also NC.) One potential source of RSEs in magmatic CC irons is the set of refractory metal nuggets from inherited CAIs. Magmatic CC‐iron groups tend to have longer cosmic‐ray exposure (CRE) ages than magmatic NC‐iron groups, indicating long residence times as small bodies in interplanetary space. The lower membership of CC‐iron groups is probably mainly due to the high oxidation state of their precursors. Such oxidation would have produced lesser amounts of free metal; parent body differentiation of such bodies would have produced smaller cores, resulting in fewer samples available to make CC‐iron meteorites in the first place. (Ungrouped magmatic irons, most of which can be considered groups with only one member, also tend to be carbonaceous.) It is possible that a subset of the chondrule‐poor dark inclusions in many carbonaceous chondrites represent unmelted materials related to the precursors of the CC irons. The Eagle Station pallasites (also CC‐related) are analogous to CC irons in being more oxidized, richer in Ni and RSEs, and fewer in number than main‐group pallasites (PMG). However, Eagle Station has a shorter CRE age than most PMG.
Tea has been shown to be a potent inhibitor of nonheme iron absorption, but it remains unclear whether the timing of tea consumption relative to a meal influences iron bioavailability.
The aim of the ...study was to investigate the effect of a 1-h time interval of tea consumption on nonheme iron absorption in an iron-containing meal in a cohort of iron-replete, nonanemic female subjects with the use of a stable isotope (
Fe).
Twelve women (mean ± SD age: 24.8 ± 6.9 y) were administered a standardized porridge meal extrinsically labeled with 4 mg
Fe as FeSO
on 3 separate occasions, with a 14-d time interval between each test meal (TM). The TM was administered with water (TM-1), with tea administered simultaneously (TM-2), and with tea administered 1 h postmeal (TM-3). Fasted venous blood samples were collected for iron isotopic analysis and measurement of iron status biomarkers. Fractional iron absorption was estimated by the erythrocyte iron incorporation method.
Iron absorption was 5.7% ± 8.5% (TM-1), 3.6% ± 4.2% (TM-2), and 5.7% ± 5.4% (TM-3). Mean fractional iron absorption was found to be significantly higher (2.2%) when tea was administered 1 h postmeal (TM-3) than when tea was administered simultaneously with the meal (TM-2) (
= 0.046). An ∼50% reduction in the inhibitory effect of tea (relative to water) was observed, from 37.2% (TM-2) to 18.1% (TM-3).
This study shows that tea consumed simultaneously with an iron-containing porridge meal leads to decreased nonheme iron absorption and that a 1-h time interval between a meal and tea consumption attenuates the inhibitory effect, resulting in increased nonheme iron absorption. These findings are not only important in relation to the management of iron deficiency but should also inform dietary advice, especially that given to those at risk of deficiency. This trial was registered at clinicaltrials.gov as NCT02365103.
In infants and young children in Sub-Saharan Africa, iron-deficiency anemia (IDA) is common, and many complementary foods are low in bioavailable iron. In-home fortification of complementary foods ...using iron-containing micronutrient powders (MNPs) and oral iron supplementation are both effective strategies to increase iron intakes and reduce IDA at this age. However, these interventions produce large increases in colonic iron because the absorption of their high iron dose (≥12.5 mg) is typically <20%. We reviewed studies in infants and young children on the effects of iron supplements and iron fortification with MNPs on the gut microbiome and diarrhea. Iron-containing MNPs and iron supplements can modestly increase diarrhea risk, and in vitro and in vivo studies have suggested that this occurs because increases in colonic iron adversely affect the gut microbiome in that they decrease abundances of beneficial barrier commensal gut bacteria (e.g., bifidobacteria and lactobacilli) and increase the abundance of enterobacteria including entropathogenic Escherichia coli. These changes are associated with increased gut inflammation. Therefore, safer formulations of iron-containing supplements and MNPs are needed. To improve MNP safety, the iron dose of these formulations should be reduced while maximizing absorption to retain efficacy. Also, the addition of prebiotics to MNPs is a promising approach to mitigate the adverse effects of iron on the infant gut.
We report the successful infusion of molten salt mixtures containing LiCl-KCl, NaCl, and NaCl-CaCl.sub.2 with UCl.sub.3 via reaction of U metal with iron chlorides (FeCl.sub.2 and FeCl.sub.3). ...Reaction in LiCl-KCl and NaCl-CaCl.sub.2 resulted in a yield of 93% and 96.7% using FeCl.sub.2 at 500 and 600 °C, respectively. Reaction to form NaCl-UCl.sub.3 at 850 °C had a yield of 70.6%. Volatilization of the oxidant may explain low yields. Reaction with the more volatile FeCl.sub.3 in NaCl-CaCl.sub.2 at 600 °C resulted in 80.7% yield. Open circuit potential measurements were made and yielded values consistent with very high selectivity for UCl.sub.3 rather than UCl.sub.4.
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.
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.
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.
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).
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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