scholarly journals Acute Consumption of Prebiotic Galacto-Oligosaccharides Increases Iron Absorption from Ferrous Fumarate, but not from Ferrous Sulfate and Ferric Pyrophosphate: Stable Iron Isotope Studies in Iron-Depleted Young Women

2020 ◽  
Vol 150 (9) ◽  
pp. 2391-2397
Author(s):  
Frederike M D Jeroense ◽  
Christophe Zeder ◽  
Michael B Zimmermann ◽  
Isabelle Herter-Aeberli

ABSTRACT Background Although acute consumption of high doses of prebiotic galacto-oligosaccharides (GOS) increases fractional iron absorption (FIA) from ferrous fumarate (FeFum), it is uncertain if low doses of GOS have this effect. Furthermore, whether GOS improve iron absorption from other commonly used iron compounds and whether ascorbic acid (AA) enhances the effect of GOS on iron absorption from FeFum is unclear. Objectives In iron-depleted women [serum ferritin (SF) <30 μg/L], we assessed: 1) whether the acute enhancing effect of GOS on FeFum is dose dependent; 2) if GOS would affect FIA from ferrous sulfate (FeSO4) or ferric pyrophosphate (FePP); and 3) if AA and GOS given together enhance FIA from FeFum to a greater extent compared with GOS alone. Methods We recruited 46 women (mean age 22.0 y, mean BMI 21.3 kg/m2, median SF 17.1 μg/L), and measured FIA from 14 mg iron labeled with stable isotopes in the following conditions: 1) FIA from FeFum given with 3.5 g, 7 g GOS, and without GOS; 2) FIA from FeSO4 and FePP given with and without 15 g GOS; and 3) FIA from FeFum given with 7 g GOS with and without 93 mg AA. FIA was measured as erythrocyte incorporation of stable isotopes after 14 d. Comparisons were made using paired samples t-test or Wilcoxon rank sum test where appropriate. Results Giving 7 g of GOS significantly increased FIA from FeFum (+26%; P = 0.039), whereas 3.5 g GOS did not (P = 0.130). GOS did not significantly increase FIA from FeSO4 (P = 0.998) or FePP (P = 0.059). FIA from FeFum given with GOS and AA was significantly higher compared with FeFum given with GOS alone (+30%; P <0.001). Conclusions In iron-depleted women, GOS does not increase FIA from FeSO4 or FePP, but it increases FIA from FeFum. Thus, a combination of FeFum and GOS may be a well-absorbed formula for iron supplements. The study was registered at clinicaltrials.gov as NCT03762148.

2020 ◽  
Vol 150 (12) ◽  
pp. 3200-3207 ◽  
Author(s):  
Nadja Mikulic ◽  
Mary A Uyoga ◽  
Edith Mwasi ◽  
Nicole U Stoffel ◽  
Christophe Zeder ◽  
...  

ABSTRACT Background Whether lactoferrin (Lf) binds iron to facilitate its absorption or to sequester iron from potential enteropathogens remains uncertain. Bovine Lf is added to many infant formulas, but previous studies in infants reported that Lf had no effect on or inhibited iron absorption. The effects of the apo (iron-free) or the holo (iron-loaded) forms of Lf on iron absorption are unclear. Objectives Our objective was to compare iron absorption from a maize-based porridge containing: 1) labeled ferrous sulfate (FeSO4) alone; 2) labeled FeSO4 given with bovine apo-Lf; and 3) intrinsically labeled bovine holo-Lf. Methods In a crossover study, we measured iron absorption in Kenyan infants (n = 25; mean ± SD age 4.2 ± 0.9 months; mean ± SD hemoglobin 109 ± 11 g/L) from maize-based test meals containing: 1) 1.5 mg of iron as 54Fe-labeled FeSO4; 2) 1.42 mg of iron as 58Fe-labeled FeSO4, given with 1.41 g apo-Lf (containing 0.08 mg iron); and 3) 1.41 g holo-Lf carrying 1.5 mg iron as 57Fe. The iron saturation levels of apo- and holo-Lf were 0.56% and 47.26%, respectively primary outcome was fractional iron absorption (FIA), assessed by erythrocyte incorporation of isotopic labels. Results The FIA from the meal containing apo-Lf + FeSO4 (geometric mean, 9.8%; −SD and +SD, 5.4% and 17.5%) was higher than from the meals containing FeSO4 (geometric mean, 6.3%; −SD and +SD, 3.2% and 12.6%; P = 0.002) or holo-Lf (geometric mean, 5.0%; −SD and +SD, 2.8% and 8.9%; P <0.0001). There was no significant difference in FIA when comparing the meals containing holo-Lf versus FeSO4 alone (P = 0.24). Conclusions The amount of iron absorbed from holo-Lf was comparable to that of FeSO4, and the addition of apo-Lf to a test meal containing FeSO4 significantly increased (+56%) iron absorption. These findings suggest that Lf facilitates iron absorption in young infants. Because Lf binds iron with high affinity, it could be a safe way to provide iron to infants in low-income countries, where iron fortificants can adversely affect the gut microbiome and cause diarrhea. This study was registered at clinicaltrials.gov as NCT03617575.


2019 ◽  
Vol 149 (5) ◽  
pp. 738-746 ◽  
Author(s):  
Frederike M D Jeroense ◽  
Ladina Michel ◽  
Christophe Zeder ◽  
Isabelle Herter-Aeberli ◽  
Michael B Zimmermann

ABSTRACTBackgroundAnimal studies suggest prebiotics can increase iron absorption, but results from human studies are equivocal.ObjectivesIn iron-depleted women, before (baseline) and after daily consumption of galacto-oligosaccharides (GOS) for 4 wk, we sought to assess fractional iron absorption (FIA) from an iron supplement given with and without single doses of GOS in test meals or water.MethodsIn all women (n = 34; median serum ferritin concentration = 16.4 µg/L), FIA from doses of 14 mg iron labeled with stable isotopes was measured in the following conditions at baseline: 1) FIA from ferrous fumarate (FeFum) in water given with and without 15 g GOS; 2) FIA from FeFum in a test meal given with and without 15 g GOS; 3) FIA from ferrous sulfate (FeSO4) in a test meal given without 15 g GOS. All subjects then consumed ∼15 g GOS daily for 4 wk. Then the following conditions were tested: 4) FIA from FeFum in a test meal with and without 15 g GOS; and 5) FIA from FeSO4 in a test meal with 15 g GOS. FIA was measured as erythrocyte incorporation of stable isotopes.ResultsAt baseline, GOS significantly increased FIA from FeFum when given with water (+61%; P < 0.001) and the meal (+28%; P = 0.002). After 4 wk of GOS consumption, GOS again significantly increased FIA from FeFum in the meal (+29%; P = 0.044). However, compared with baseline, consumption of GOS for 4 wk did not significantly enhance absorption from FeFum in the meal given without GOS. FIA from FeSO4 given with GOS in a meal after 4 wk of GOS consumption was not significantly greater than FIA from FeSO4 in a meal without GOS at baseline.ConclusionsIn iron-depleted women, GOS given with FeFum increases FIA, but 4 wk of GOS consumption did not enhance this effect. The study was registered at clinicaltrials.gov as NCT03325270.


1972 ◽  
Vol 55 (1) ◽  
pp. 197-199
Author(s):  
Gwendolyn W Pla ◽  
James C Fritz

Abstract A study was conducted to determine the effects of certain dietary components on iron absorption in human subjects. Iron absorption was measured by plasma iron responses following test doses of iron as ferrous sulfate or ferric pyrophosphate alone or with egg, enriched white bread, or ascorbic acid. The effects of egg on iron absorption were inconclusive. Phytates at the level present in enriched white bread had no adverse effects and 500 mg ascorbic acid proved beneficial.


2018 ◽  
Vol 1 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Darío Acuña-Castroviejo ◽  
Maria T Noguiera-Navarro ◽  
Russel J Reiter ◽  
Germaine Escames

Due to the broad distribution of extrapineal melatonin in multiple organs and tissues, we analyzed the presence and subcellular distribution of the indoleamine in the heart of rats. Groups of sham-operated and pinealectomized rats were sacrificed at different times along the day, and the melatonin content in myocardial cell membranes, cytosol, nuclei and mitochondria, were measured. Other groups of control animals were treated with different doses of melatonin to monitor its intracellular distribution. The results show that melatonin levels in the cell membrane, cytosol, nucleus, and mitochondria vary along the day, without showing a circadian rhythm. Pinealectomized animals trend to show higher values than sham-operated rats. Exogenous administration of melatonin yields its accumulation in a dose-dependent manner in all subcellular compartments analyzed, with maximal concentrations found in cell membranes at doses of 200 mg/kg bw melatonin. Interestingly, at dose of 40 mg/kg b.w, maximal concentration of melatonin was reached in the nucleus and mitochondrion. The results confirm previous data in other rat tissues including liver and brain, and support that melatonin is not uniformly distributed in the cell, whereas high doses of melatonin may be required for therapeutic purposes.


Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 615
Author(s):  
Martin Doseděl ◽  
Eduard Jirkovský ◽  
Kateřina Macáková ◽  
Lenka Krčmová ◽  
Lenka Javorská ◽  
...  

Vitamin C (L-ascorbic acid) has been known as an antioxidant for most people. However, its physiological role is much larger and encompasses very different processes ranging from facilitation of iron absorption through involvement in hormones and carnitine synthesis for important roles in epigenetic processes. Contrarily, high doses act as a pro-oxidant than an anti-oxidant. This may also be the reason why plasma levels are meticulously regulated on the level of absorption and excretion in the kidney. Interestingly, most cells contain vitamin C in millimolar concentrations, which is much higher than its plasma concentrations, and compared to other vitamins. The role of vitamin C is well demonstrated by miscellaneous symptoms of its absence—scurvy. The only clinically well-documented indication for vitamin C is scurvy. The effects of vitamin C administration on cancer, cardiovascular diseases, and infections are rather minor or even debatable in the general population. Vitamin C is relatively safe, but caution should be given to the administration of high doses, which can cause overt side effects in some susceptible patients (e.g., oxalate renal stones). Lastly, analytical methods for its determination with advantages and pitfalls are also discussed in this review.


1999 ◽  
Vol 34 (5) ◽  
pp. 685-686 ◽  
Author(s):  
Kevin L Wallace ◽  
Steven C Curry ◽  
Frank LoVecchio ◽  
Robert A Raschke

1975 ◽  
Vol 66 (3) ◽  
pp. 375-383 ◽  
Author(s):  
G. VANDEPUTTE-VAN MESSOM ◽  
G. PEETERS

SUMMARY During water diuresis in conscious goats, noradrenaline (NA), its antagonists phentolamine, phenoxybenzamine and propranolol and also atropine were administered into the 3rd ventricle. The subsequent effects on water diuresis and on the excretion rates of Na+, K+ and Cl− were investigated. Infusion of NA into the 3rd ventricle induced a strong and significant antidiuretic response and a decrease in the Na+: K+ excretion ratio; these effects were dose-dependent. High doses of NA produced a significant increase in urinary K+ excretion. Similar results were observed after i.v. administration of arginine-vasopressin. Pretreatment with phentolamine injected into the 3rd ventricle produced a dose-dependent inhibition of the NA-induced antidiuretic effects. Phenoxybenzamine also blocked the response to NA but a dose-response relationship was not apparent. Atropine and propranolol did not block the response to NA.


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