Oral Iron Absorption of Ferric Citrate in Haemodialysis Patients: The Prospective, Multicentre, Observational R-OIAT Study

There are at least 40 oral iron preparations available to the prescriber; some contain iron alone, others have in addition haematinics, vitamins or substances claimed to promote iron absorption. For many there are optimistic claims concerning the incidence of gastro-intestinal side effects.

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An intensified training schedule in recreational male runners is associated with increases in erythropoiesis and inflammation and a net reduction in plasma hepcidin

American Journal of Clinical Nutrition ◽

10.1093/ajcn/nqy247 ◽

2018 ◽

Vol 108 (6) ◽

pp. 1324-1333 ◽

Cited By ~ 6

Author(s):

Diego Moretti ◽

Samuel Mettler ◽

Christophe Zeder ◽

Carsten Lundby ◽

Anneke Geurts-Moetspot ◽

...

Keyword(s):

Exercise Training ◽

Iron Absorption ◽

Iron Status ◽

Geometric Mean ◽

Iron Bioavailability ◽

Oral Iron ◽

Low Grade ◽

Hemoglobin Mass ◽

Low Grade Inflammation ◽

Iron Utilization

ABSTRACT Background Iron status is a determinant of physical performance, but training may induce both low-grade inflammation and erythropoiesis, exerting opposing influences on hepcidin and iron metabolism. To our knowledge, the combined effects on iron absorption and utilization during training have not been examined directly in humans. Objective We hypothesized that 3 wk of exercise training in recreational male runners would decrease oral iron bioavailability by increasing inflammation and hepcidin concentrations. Design In a prospective intervention, nonanemic, iron-sufficient men (n = 10) completed a 34-d study consisting of a 16-d control phase and a 22-d exercise-training phase of 8 km running every second day. We measured oral iron absorption and erythroid iron utilization using oral 57Fe and intravenous 58Fe tracers administered before and during training. We measured hemoglobin mass (mHb) and total red blood cell volume (RCV) by carbon monoxide rebreathing. Iron status, interleukin-6 (IL-6), plasma hepcidin (PHep), erythropoietin (EPO), and erythroferrone were measured before, during, and after training. Results Exercise training induced inflammation, as indicated by an increased mean ± SD IL-6 (0.87 ± 1.1 to 5.17 ± 2.2 pg/mL; P < 0.01), while also enhancing erythropoiesis, as indicated by an increase in mean EPO (0.66 ± 0.42 to 2.06 ± 1.6 IU/L), mHb (10.5 ± 1.6 to 10.8 ± 1.8 g/kg body weight), and mean RCV (30.7 ± 4.3 to 32.7 ± 4.6 mL/kg) (all P < 0.05). Training tended to increase geometric mean iron absorption by 24% (P = 0.083), consistent with a decreased mean ± SD PHep (7.25 ± 2.14 to 5.17 ± 2.24 nM; P < 0.05). The increase in mHb and erythroid iron utilization were associated with the decrease in PHep (P < 0.05). Compartmental modeling indicated that iron for the increase in mHb was obtained predominantly (>80%) from stores mobilization rather than from increased dietary absorption. Conclusions In iron-sufficient men, mild intensification of exercise intensity increases both inflammation and erythropoiesis. The net effect is to decrease hepcidin concentrations and to tend to increase oral iron absorption. This trial was registered at clinicaltrials.gov as NCT01730521.

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Oral iron supplements increase hepcidin and decrease iron absorption from daily or twice-daily doses in iron-depleted young women

Blood ◽

10.1182/blood-2015-05-642223 ◽

2015 ◽

Vol 126 (17) ◽

pp. 1981-1989 ◽

Cited By ~ 184

Author(s):

Diego Moretti ◽

Jeroen S. Goede ◽

Christophe Zeder ◽

Markus Jiskra ◽

Vaiya Chatzinakou ◽

...

Keyword(s):

Young Women ◽

Transferrin Receptor ◽

Iron Absorption ◽

Oral Iron ◽

Soluble Transferrin Receptor ◽

Iron Supplements ◽

Key Points

Key Points Iron supplements at doses of 60 mg Fe as FeSO4 or higher increase hepcidin for up to 24 hours and are associated with lower iron absorption on the following day. The soluble transferrin receptor/ferritin ratio and hepcidin are equivalent predictors of iron absorption from supplements.

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Iron absorption from oral iron supplements given on consecutive versus alternate days in iron-depleted women

BMJ evidence-based medicine ◽

10.1136/bmjebm-2018-111013 ◽

2018 ◽

Vol 23 (6) ◽

pp. 228-229

Author(s):

Thomas M Goodsall ◽

Tim Walker

Keyword(s):

Iron Absorption ◽

Oral Iron ◽

Iron Supplements

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The effect of iron dosing schedules on plasma hepcidin and iron absorption in Kenyan infants

American Journal of Clinical Nutrition ◽

10.1093/ajcn/nqaa174 ◽

2020 ◽

Vol 112 (4) ◽

pp. 1132-1141 ◽

Cited By ~ 1

Author(s):

Mary A Uyoga ◽

Nadja Mikulic ◽

Daniela Paganini ◽

Edith Mwasi ◽

Nicole U Stoffel ◽

...

Keyword(s):

Prospective Studies ◽

Iron Absorption ◽

Geometric Mean ◽

Oral Iron ◽

Iron Isotopes ◽

Iron Supplement ◽

Micronutrient Powder

ABSTRACT Background In adults, oral iron doses increase plasma hepcidin (PHep) for 24 h, but not for 48 h, and there is a circadian increase in PHep over the day. Because high PHep decreases fractional iron absorption (FIA), alternate day iron dosing in the morning may be preferable to consecutive day dosing. Whether these effects occur in infants is uncertain. Objective Using stable iron isotopes in Kenyan infants, we compared FIA from morning and afternoon doses and from consecutive, alternate (every second day) and every third day iron doses. Methods In prospective studies, we measured and compared FIA and the PHep response from 1) meals fortified with a 12-mg iron micronutrient powder given in the morning or afternoon (n = 22); 2) the same given on consecutive or alternate days (n = 21); and 3) a 12-mg iron supplement given on alternate days or every third day (n = 24). Results In total, 65.7% of infants were anemic. In study 1, PHep did not differ between morning and afternoon (P = 0.072), and geometric mean FIA[−SD, +SD](%) did not differ between the morning and afternoon doses [15.9 (8.9, 28.6) and 16.1 (8.7, 29.8), P = 0.877]. In study 2, PHep was increased 24 h after oral iron (P = 0.014), and mean FIA [±SD](%) from the baseline dose [23.3 (10.9)] was greater than that from the consecutive day dose (at 24 h) [20.1 (10.4); P = 0.042] but did not differ from the alternate day dose (at 48 h) [20.9 (13.4); P = 0.145]. In study 3, PHep was not increased 48 and 72 h after oral iron (P = 0.384), and the geometric mean FIA[−SD, +SD](%) from doses given at baseline, alternate days, and every third day did not differ [12.7 (7.3, 21.9), 13.8 (7.8, 24.2), and 14.8 (8.8, 24.8), respectively; P = 0.080]. Conclusions In Kenyan infants given 12 mg oral iron, morning and afternoon doses are comparably absorbed, dosing on consecutive days increases PHep and modestly decreases iron absorption compared with alternate day dosing, and dosing on alternate days or every third day does not increase PHep or decrease absorption. This trial was registered at clinicaltrials.gov as NCT02989311 and NCT03617575.

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Novel Iron-Whey Protein Microspheres Protect Gut Epithelial Cells from Iron-Related Oxidative Stress and Damage and Improve Iron Absorption in Fasting Adults

Acta Haematologica ◽

10.1159/000480632 ◽

2017 ◽

Vol 138 (4) ◽

pp. 223-232 ◽

Cited By ~ 3

Author(s):

Jun Wang ◽

Gabor Radics ◽

Michael Whelehan ◽

Aoibhe OʼDriscoll ◽

Anne Marie Healy ◽

...

Keyword(s):

Epithelial Cells ◽

Whey Protein ◽

Serum Iron ◽

Iron Absorption ◽

Ferrous Sulphate ◽

Oral Iron ◽

High Dose ◽

Food Fortification ◽

Iron Depletion ◽

Baseline Serum

Background: Iron food fortification and oral iron formulations are frequently limited by poor absorption, resulting in the widespread use of high-dose oral iron, which is poorly tolerated. Methods: We evaluated novel iron-denatured whey protein (Iron-WP) microspheres on reactive oxygen species (ROS) and viability in gut epithelial (HT29) cells. We compared iron absorption from Iron-WP versus equimolar-dose (25 mg elemental iron) ferrous sulphate (FeSO4) in a prospective, randomised, cross-over study in fasting volunteers (n = 21 per group) dependent on relative iron depletion (a ferritin level ≤/>30 ng/mL). Results: Iron-WP caused less ROS generation and better HT29 cell viability than equimolar FeSO4. Iron-WP also showed better absorption with a maximal 149 ± 39% increase in serum iron compared to 65 ± 14% for FeSO4 (p = 0.01). The response to both treatments was dependent on relative iron depletion, and multi-variable analysis showed that better absorption with Iron-WP was independent of baseline serum iron, ferritin, transferrin saturation, and haemoglobin in the overall group and in the sub-cohort with relative iron depletion at baseline (p < 0.01). Conclusions: Novel Iron-WP microspheres may protect gut epithelial cells and improve the absorption of iron versus FeSO4. Further evaluation of this approach to food fortification and supplementation with iron is warranted.

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Iron Absorption after Single Pharmacological Oral Iron Loading Test in Patients on Chronic Peritoneal Dialysis and in Healthy Volunteers

Peritoneal Dialysis International ◽

10.1177/089686080002000614 ◽

2000 ◽

Vol 20 (6) ◽

pp. 662-666 ◽

Cited By ~ 5

Author(s):

Bahar Bastani ◽

Shah Islam ◽

Nasser Boroujerdi

Keyword(s):

Serum Iron ◽

Iron Absorption ◽

Iron Concentration ◽

Significant Rise ◽

Oral Iron ◽

Iron Sulfate ◽

Chronic Peritoneal Dialysis ◽

Dialysis Patients ◽

Control Subjects ◽

Serum Iron Concentration

Objective Oral iron is poorly absorbed in chronic dialysis patients. We tested the hypothesis that a superpharmacologic dose of iron sulfate (260 mg elemental iron) administered on an empty stomach results in significant iron absorption in these patients. Design A prospective open controlled trial. Setting Outpatient department of a university hospital. Patients Nine stable chronic peritoneal dialysis (PD) patients and seven normal control subjects. Method All subjects ingested a single dose of 4 tablets of iron sulfate (260 mg elemental iron total) in the morning while fasting. Outcome Measures Serum iron concentrations at baseline, and at 2 and 4 hours after the oral dose were compared between the two groups. Results The control group showed a significant rise in mean [± standard error (SE)] serum iron concentration, from a baseline value of 76.5 ± 7 μg/dL to 191 ± 10.5 μg/dL at 2 hours and to 190 ± 24 μg/dL at 4 hours. This result represents a percentage rise of 164% ± 32% at 2 hours and 152% ± 28.5% at 4 hours. In the PD patients, a significant rise in serum iron concentration was also seen, from a baseline value of 64 ± 8 μg/dL to 130 ± 3 μg/dL at 2 hours and 111 ± 18 μg/dL at 4 hours. This result represents a percentage rise of 105% ± 29% at 2 hours and 77% ± 23.5% at 4 hours. However, the absolute change in serum iron concentration in PD patients at 2 and 4 hours was approximately equal to 50% of the change in control subjects at those time points. None of the PD patients experienced gastrointestinal side effects; 4 control subjects experienced mild side effects. Conclusion Despite impaired oral iron absorption in chronic dialysis patients, a large pharmacologic dose given orally can result in significant iron absorption and may prove to be a more efficient means of oral iron supplementation therapy in these patients.

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