Effects of alterations in cellular iron on biosynthesis of the transferrin receptor in K562 cells

1985 ◽  
Vol 5 (4) ◽  
pp. 595-600
Author(s):  
K K Rao ◽  
D Shapiro ◽  
E Mattia ◽  
K Bridges ◽  
R Klausner
Keyword(s):  
K562 Cells ◽  
Fold Increase ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Cellular Iron ◽  
Erythroleukemia Cell ◽  
Ferric Ammonium ◽  
Translatable Mrna ◽  
In Cells

Treatment of K562 cells, a human erythroleukemia cell line, with desferrioxamine raised the levels of the receptor for transferrin (Tf) two- to threefold over that of the control cells. The levels of receptor were reduced by at least 50 and 35% of that of the control in cells treated with diferric Tf and ferric ammonium citrate, respectively. These changes were of total cellular receptors with no alteration in the proportion of receptors found on the cell surface. The half-lives of the receptor were identical in cells treated with desferrioxamine, diferric Tf, or ferric ammonium citrate. Cells metabolically labeled with [35S]methionine showed a 2.5-fold increase in the rate of receptor synthesis when treated with desferrioxamine and a 35 and 65% decrease when treated with ferric ammonium citrate and diferric Tf, respectively. In vitro translations of polyadenylated mRNA isolated from cells incubated with desferrioxamine showed a 2.5-fold increase in translatable mRNA for the receptor, whereas treatment of cells with ferric ammonium citrate and diferric Tf resulted in a 25 and 50% reduction, respectively, in translatable mRNA for this receptor.

scholarly journals Effects of alterations in cellular iron on biosynthesis of the transferrin receptor in K562 cells.

1985 ◽  
Vol 5 (4) ◽  
pp. 595-600 ◽  
Author(s):  
K K Rao ◽  
D Shapiro ◽  
E Mattia ◽  
K Bridges ◽  
R Klausner
Keyword(s):  
K562 Cells ◽  
Fold Increase ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Cellular Iron ◽  
Erythroleukemia Cell ◽  
Ferric Ammonium ◽  
Translatable Mrna ◽  
In Cells

Treatment of K562 cells, a human erythroleukemia cell line, with desferrioxamine raised the levels of the receptor for transferrin (Tf) two- to threefold over that of the control cells. The levels of receptor were reduced by at least 50 and 35% of that of the control in cells treated with diferric Tf and ferric ammonium citrate, respectively. These changes were of total cellular receptors with no alteration in the proportion of receptors found on the cell surface. The half-lives of the receptor were identical in cells treated with desferrioxamine, diferric Tf, or ferric ammonium citrate. Cells metabolically labeled with [35S]methionine showed a 2.5-fold increase in the rate of receptor synthesis when treated with desferrioxamine and a 35 and 65% decrease when treated with ferric ammonium citrate and diferric Tf, respectively. In vitro translations of polyadenylated mRNA isolated from cells incubated with desferrioxamine showed a 2.5-fold increase in translatable mRNA for the receptor, whereas treatment of cells with ferric ammonium citrate and diferric Tf resulted in a 25 and 50% reduction, respectively, in translatable mRNA for this receptor.

scholarly journals New advances in thein-vitroculture ofDientamoeba fragilis

Parasitology ◽  
2012 ◽  
Vol 139 (7) ◽  
pp. 864-869 ◽  
Author(s):  
VARUNI S. MUNASINGHE ◽  
D. STARK ◽  
J. T. ELLIS
Keyword(s):  
Culture Medium ◽  
Fold Increase ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Intestinal Protozoan ◽  
Dientamoeba Fragilis ◽  
Cell Counts ◽  
Ferric Ammonium ◽  
Gastrointestinal Complaints

SUMMARYDientamoeba fragilisis an intestinal protozoan in humans that is commonly associated with diarrhoea and other gastrointestinal complaints. Studies conducted to investigate the biology of this parasite are limited by methods forin vitrocultivation. The objective of this study was to improve a biphasic culture medium, based on the Loeffler's slope, by further supplementation in order to increase the yield of trophozoites in culture. The currentin vitroculture ofD. fragilisis a xenic culture with a mix of bacteria. Three different liquid overlays were evaluated including Earle's balanced salt solution (EBSS), PBS and Dulbecco's modified PBS (DPBS), for their ability to support thein vitrogrowth ofD. fragilistrophozoites. Out of these 3 overlays EBSS gave the highest increase in the trophozoite numbers. The effect of supplementation was analysed by supplementing EBSS with ascorbic acid, ferric ammonium citrate, L-cysteine, cholesterol and alpha-lipoic acid and quantification ofin vitrogrowth by cell counts. A new liquid overlay is here described based upon EBSS supplemented with cholesterol and ferric ammonium citrate that, in conjunction with the Loeffler's slope, supports the growth ofD. fragilistrophozoitesin vitro. This modified overlay supported a 2-fold increase in the numbers of trophozoite in culture from all 4D. fragilisisolates tested, when compared to a PBS overlay. These advances enable the harvest of a larger number of trophozoites needed for further studies on this parasite.

scholarly journals Persistence of contamination of hens' egg albumen in vitro with Salmonella serotypes

1992 ◽  
Vol 108 (3) ◽  
pp. 389-396 ◽  
Author(s):  
J. L. Lock ◽  
R. G. Board
Keyword(s):  
Cell Membrane ◽  
Glucose Concentration ◽  
Salmonella Enteritidis ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Egg Albumen ◽  
Ferric Ammonium ◽  
Salmonella Serotypes

SUMMARYA study was made of the persistence of different Salmonella serotypes in hens' egg albumen in vitro at 4, 20 and 30 °C. The majority of serotypes remained viable but did not increase in numbers at 20 and 30 °C for 42 days. At 4 °C many of the serotypes died out.The addition of ferric ammonium citrate on the 42nd day of incubation induced multiplication of organisms incubated at 20 and 30 °C, but not at 4 °C. The pH and glucose concentration of the albumen diminished only when heavy growth occurred.Salmonella enteritidis remained viable on the air cell membrane in vitro for 17 days at 4, 20 and 30 °C. Thirty percent of the organisms also remained motile in albumen for 42 days at 25 °C and up to 5% of the cells remained motile for up to 20 days at 4 °C.

Protoporphyrin IX Down-Regulates DMT1 Associated Protein (DAP) in K562 Cells.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1548-1548
Author(s):  
Yasumasa Okazaki ◽  
Hong Yin ◽  
Yuxiang Ma ◽  
Mary Yeh ◽  
Kwo-yih Yeh ◽  
...  
Keyword(s):  
Iron Metabolism ◽  
Iron Content ◽  
Iron Status ◽  
Protoporphyrin Ix ◽  
K562 Cells ◽  
Erythroid Differentiation ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Down Regulation ◽  
Cellular Iron

Abstract The final steps of heme biosynthesis include the transport of coproporphyrin with the transport step probably mediated by the peripheral benzodiazepine receptor (PBR). Within the mitochondria copropoprhyrin is then converted to protoporphyrin IX (PPIX) which in turn is converted to hemin with insertion of iron by ferrochelatase. PBR is ubiquitously expressed and has been implicated in steriodogenesis, apoptosis, erythroid differentiation, and inflammation. Interestingly, PPIX is among several high affinity ligands for PBR. Various cytosolic proteins that interact with PBR have also been defined including PBR associated protein 7 (PAP7). The various PBR ligands including PPIX may affect the binding of these proteins to PBR. We have demonstrated (Blood, Nov 2004; 104: 53) that DAP, a protein highly homologous to PAP7, binds to the C-terminus of DMT1 and may have a role in regulation of intracellular iron transport. We, therefore, examined the effects of PPIX on the functions of DAP and other proteins that affect cellular iron metabolism. DAP is 526 amino acid protein with a nuclear localization signal domain (aa 212–229) and a Golgi localization domain (aa 380–524), and is distributed in the cytoplasm, Golgi apparatus, and nuclei of K562 cells. K562 cells were grown in the presence of 5 μM PPIX for 24 hours and then the expression of DAP, transferrin receptor 1 (TfR1), and ferritin examined by western blot analysis. In addition, cells were grown in medium of either normal iron content (3.5 μM from ferri-transferrin), high iron content (217 μM from the addition of ferric ammonium citrate), or low iron content (by the addition of 50 mM desferroxamine). Under all three iron conditions PPIX induced differentiation but down-regulated ferritin expression and up-regulated TfR1 expression. Additionally, PPIX had a striking effect on DAP expression markedly decreasing DAP levels but only in cells grown either in normal or low iron medium. In addition, PPIX affected the expression of the iron transporter DMT1in parallel with DAP. As PPIX induced erythroid differentiation of K562 cells we examined the effects of hemin which can also induce differentiation of K562 cells. In contrast to PPIX, hemin caused strong down-regulation of TfR and up-regulation of ferritin and DAP. The down-regulation of DAP induced by PPIX was restored by the addition of hemin. These results indicate that PPIX affects DAP expression and other important elements involved in cellular iron metabolism and that these effects are partially modified by the iron status of the cell.

Chemicals That Stimulate Iron Uptake – A Novel Approach to Treatment of Iron Deficiency,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3180-3180
Author(s):  
Zhen Li
Keyword(s):  
Iron Deficiency ◽  
Small Molecules ◽  
Iron Uptake ◽  
Iron Absorption ◽  
K562 Cells ◽  
Divalent Metal ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Caco2 Cells ◽  
Ferric Ammonium

Abstract 3180 Iron (Fe) is an essential nutrient required for all cells, especially for erythrocyte hemoglobin synthesis which requires absorption of 1–2 mg of iron from the gastrointestinal tract. Iron deficiency as a result of inadequate dietary uptake has multiple consequences including anemia and abnormal neurologic development in children and is a global public health concern. Enterocytes in the duodenum, the site of iron absorption, can extract about 10% of dietary Fe. Nonetheless for numerous reasons simple iron supplementation has not solved the worldwide epidemic of iron deficiency. We hypothesized that small molecules which could potentiate iron uptake into cells would allow enterocytes to absorb an increased amount of dietary iron and could be beneficial in limiting iron deficiency. To identify molecules that would accelerate Fe uptake we used a high through-put screening system in conjunction with a reporter system of K562 cells loaded with the divalent metal chelator calcein whose fluorescence is quenched with chelation of Fe2+. Small molecules that stimulated Fe uptake were defined as causing increased calcein fluorescence quenching compared to Fe alone. K562 cells were exposed to 0.1 μM calcein for 10 minutes, thoroughly washed, and 1 × 105 cells plated into each well of multiple 96-well plates. After equilibration of the plates at 37° C, aliquots of the individual components of an in-house chemical library of ∼12,000 compounds dissolved in DMSO were screened in duplicate or triplicate and fluorescence measurements made at 0 and 30 min after addition of 10 μM FeNH4SO4 in a Synergy IV plate reader. 30 chemicals were identified that stimulated iron-induced quenching of calcein fluorescence. The stimulation was verified by dose response curves and by assaying the effect on non-transferrin bound 55Fe uptake. None of the stimulators were cytotoxic for up to at least 3 days. The lead compound, LS081, had an IC50 = 1.22 ± 0.48 μM for 55Fe uptake in K562 cells compared to controls. LS081 was also used to examine the iron uptake in Caco2 cells grown in bicameral chambers, a model system to study intestinal iron absorption. LS081 significantly increased 55Fe uptake into Caco2 cells with a very rapid influx of 55Fe in the first 5 min after Fe was offered to the apical surface followed by a ∼ 4-fold increased uptake over the next 90 min. 55Fe transport across the basolateral surface into the basal chamber also increased ∼ 4 fold. The increased 55Fe transport in caco2 cells is more prominent at lower pH of 5.5 compare to pH 7.5 suggesting LS081 acted on a common divalent metal uptake pathway. Mice treated with LS081 + ferric ammonium citrate via oral gavage for two weeks significantly increased (p < 0.001 by unpaired t-test compared to ferric ammonium citrate alone) the level of ferritin, the iron storage protein, in the liver, demonstrating the absorption of LS081 from intestinal cells. In summary, using high through-put screening technique we identified small molecules that stimulate iron uptake and could be used as a drug for iron deficiency. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Ferric citrate decreases ruminal hydrogen sulphide concentrations in feedlot cattle fed diets high in sulphate

2013 ◽  
Vol 111 (2) ◽  
pp. 261-269 ◽  
Author(s):  
Mary E. Drewnoski ◽  
Perry Doane ◽  
Stephanie L. Hansen
Keyword(s):  
Hydrogen Sulphide ◽  
Rumen Fluid ◽  
Control Diet ◽  
Gas Production ◽  
Feedlot Cattle ◽  
Ferric Citrate ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Ferric Ammonium

Dissimilatory reduction of sulphate by sulphate-reducing bacteria in the rumen produces sulphide, which can lead to a build-up of the toxic gas hydrogen sulphide (H2S) in the rumen when increased concentrations of sulphate are consumed by ruminants. We hypothesised that adding ferric Fe would competitively inhibit ruminal sulphate reduction. The effects of five concentrations and two sources (ferric citrate or ferric ammonium citrate) of ferric Fe were examinedin vitro(n6 per treatment). Rumen fluid was collected from a steer that was adapted to a high-concentrate, high-sulphate diet (0·51 % S). The addition of either source of ferric Fe decreased (P< 0·01) H2S concentrations without affecting gas production (P= 0·38), fluid pH (P= 0·80) orin vitroDM digestibility (P= 0·38) after a 24 h incubation. Anin vivoexperiment was conducted using eight ruminally fistulated steers (543 (sem12) kg) in a replicated Latin square with four periods and four treatments. The treatments included a high-concentrate, high-sulphate control diet (0·46 % S) or the control diet plus ferric ammonium citrate at concentrations of 200, 300 or 400 mg Fe/kg diet DM. The inclusion of ferric Fe did not affect DM intake (P= 0·21). There was a linear (P< 0·01) decrease in the concentration of ruminal H2S as the addition of ferric Fe concentrations increased. Ferric citrate appears to be an effective way to decrease ruminal H2S concentrations, which could allow producers to safely increase the inclusion of ethanol co-products.

scholarly journals Iron robbery by intracellular pathogen via bacterial effector–induced ferritinophagy

2021 ◽  
Vol 118 (23) ◽  
pp. e2026598118
Author(s):  
Qi Yan ◽  
Wenqing Zhang ◽  
Mingqun Lin ◽  
Omid Teymournejad ◽  
Khemraj Budachetri ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Host Cell ◽  
Host Cells ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Type Iv ◽  
Cellular Iron ◽  
Ferric Ammonium ◽  
Iron Pool ◽  
Human Monocytic Ehrlichiosis

Iron is essential for survival and proliferation of Ehrlichia chaffeensis, an obligatory intracellular bacterium that causes an emerging zoonosis, human monocytic ehrlichiosis. However, how Ehrlichia acquires iron in the host cells is poorly understood. Here, we found that native and recombinant (cloned into the Ehrlichia genome) Ehrlichia translocated factor-3 (Etf-3), a previously predicted effector of the Ehrlichia type IV secretion system (T4SS), is secreted into the host cell cytoplasm. Secreted Etf-3 directly bound ferritin light chain with high affinity and induced ferritinophagy by recruiting NCOA4, a cargo receptor that mediates ferritinophagy, a selective form of autophagy, and LC3, an autophagosome biogenesis protein. Etf-3−induced ferritinophagy caused ferritin degradation and significantly increased the labile cellular iron pool, which feeds Ehrlichia. Indeed, an increase in cellular ferritin by ferric ammonium citrate or overexpression of Etf-3 or NCOA4 enhanced Ehrlichia proliferation, whereas knockdown of Etf-3 in Ehrlichia via transfection with a plasmid encoding an Etf-3 antisense peptide nucleic acid inhibited Ehrlichia proliferation. Excessive ferritinophagy induces the generation of toxic reactive oxygen species (ROS), which could presumably kill both Ehrlichia and host cells. However, during Ehrlichia proliferation, we observed concomitant up-regulation of Ehrlichia Fe-superoxide dismutase, which is an integral component of Ehrlichia T4SS operon, and increased mitochondrial Mn-superoxide dismutase by cosecreted T4SS effector Etf-1. Consequently, despite enhanced ferritinophagy, cellular ROS levels were reduced in Ehrlichia-infected cells compared with uninfected cells. Thus, Ehrlichia safely robs host cell iron sequestered in ferritin. Etf-3 is a unique example of a bacterial protein that induces ferritinophagy to facilitate pathogen iron capture.

scholarly journals A study on the aspects of pharmacoepidemiology and pharmacohaemovigilance of ferrous ascorbate, ferrous fumarate, ferrous sulphate and ferric ammonium citrate, among the rural anaemic women, in the Indian spectrum

2019 ◽  
Vol 8 (12) ◽  
pp. 2751
Author(s):  
Moumita Hazra
Keyword(s):  
Ferrous Sulphate ◽  
Haemoglobin Concentration ◽  
Significant Rise ◽  
Demographic Characteristics ◽  
Health Concern ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Ferrous Fumarate ◽  
Ferrous Ascorbate ◽  
Ferric Ammonium

Background: Anaemia is a global health concern, associated with increased maternal and perinatal mortality, preterm delivery, low birth weight, extreme fatigue and impaired immune system; and controlled by oral haematinics; with a rise in haemoglobin concentration. The objective was to examine the various aspects of pharmacoepidemiology and pharmacohaemovigilance of oral haematinics, among the anaemic women population, in rural India.Methods: This was a multi-centre, retrospective, observational and analytical study of the hospital medical records of 250 anaemic patients, who were allocated into group A of 125 patients within 15-21 years and group B of 125 patients within 22-35 years. The patients were prescribed oral haematinics, containing 60 mg of elemental iron, thrice daily, with meals. The various aspects of pharmacoepidemiology and pharmacohaemovigilance of ferrous ascorbate, ferrous sulphate, ferrous fumarate and ferric ammonium citrate, including patients’ demographic characteristics, anaemic symptoms assessment, prescription patterns, and safety assessment, on 1st, 2nd, 3rd months and follow-up visits, were recorded and thoroughly analysed..Results: In groups A and B, the demographic characteristics of the patients were comparable; ferrous ascorbate was the most commonly prescribed oral haematinic, followed by ferrous sulphate, ferrous fumarate and ferric ammonium citrate, which controlled mild to moderate iron deficiency anaemia, with a gradual significant rise in haemoglobin concentration, in the successive 3 months; and adverse effects were observed to be statistically non-significant in either group.Conclusions: The different aspects of pharmacoepidemiology and pharmacohaemovigilance in the study established that the oral haematinics were reasonably beneficial and safe among the anaemic women population, in rural India.

Sign in / Sign up

Export Citation Format

Share Document