scholarly journals Iron as the Key Modulator of Hepcidin Expression in Erythroid Antibody-Mediated Hypoplasia

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
J. C. Fernandes ◽  
P. Garrido ◽  
S. Ribeiro ◽  
P. Rocha-Pereira ◽  
E. Bronze-da-Rocha ◽  
...  
Keyword(s):  
Serum Iron ◽  
Rare Complication ◽  
Therapeutic Strategies ◽  
Divalent Metal Transporter 1 ◽  
Divalent Metal Transporter ◽  
Hepcidin Expression ◽  
Metal Transporter ◽  
Human Erythropoietin ◽  
Underlying Mechanisms ◽  
The Impact

Erythroid hypoplasia (EH) is a rare complication associated with recombinant human erythropoietin (rHuEPO) therapies, due to development of anti-rHuEPO antibodies; however, the underlying mechanisms remain poorly clarified. Our aim was to manage a rat model of antibody-mediated EH induced by rHuEPO and study the impact on iron metabolism and erythropoiesis. Wistar rats treated during 9 weeks with a high rHuEPO dose (200 IU) developed EH, as shown by anemia, reduced erythroblasts, reticulocytopenia, and plasmatic anti-rHuEPO antibodies. Serum iron was increased and associated with mRNA overexpression of hepatic hepcidin and other iron regulatory mediators and downregulation of matriptase-2; overexpression of divalent metal transporter 1 and ferroportin was observed in duodenum and liver. DecreasedEPOexpression was observed in kidney and liver, while EPO receptor was overexpressed in liver. Endogenous EPO levels were normal, suggesting that anti-rHuEPO antibodies blunted EPO function. Our results suggest that anti-rHuEPO antibodies inhibit erythropoiesis causing anemia. This leads to a serum iron increase, which seems to stimulate hepcidin expression despite no evidence of inflammation, thus suggesting iron as the key modulator of hepcidin synthesis. These findings might contribute to improving new therapeutic strategies against rHuEPO resistance and/or development of antibody-mediated EH in patients under rHuEPO therapy.

scholarly journals Decreased hepatic iron in response to alcohol may contribute to alcohol-induced suppression of hepcidin

2016 ◽  
Vol 115 (11) ◽  
pp. 1978-1986 ◽  
Author(s):  
Joe Varghese ◽  
Jithu Varghese James ◽  
Sreerohini Sagi ◽  
Subhosmito Chakraborty ◽  
Abitha Sukumaran ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Time Course ◽  
Histopathological Examination ◽  
Divalent Metal Transporter 1 ◽  
Divalent Metal Transporter ◽  
Hepcidin Expression ◽  
Cytochrome P4502e1 ◽  
Metal Transporter ◽  
Serum Hepcidin ◽  
Time Course Study

AbstractHepatic Fe overload has often been reported in patients with advanced alcoholic liver disease. However, it is not known clearly whether it is the effect of alcohol that is responsible for such overload. To address this lacuna, a time-course study was carried out in mice in order to determine the effect of alcohol on Fe homoeostasis. Male Swiss albino mice were pair-fed Lieber–DeCarli alcohol diet (20 % of total energy provided as alcohol) for 2, 4, 8 or 12 weeks. Expression levels of duodenal and hepatic Fe-related proteins were determined by quantitative PCR and Western blotting, as were Fe levels and parameters of oxidative stress in the liver. Alcohol induced cytochrome P4502E1 and oxidative stress in the liver. Hepatic Fe levels and ferritin protein expression dropped to significantly lower levels after 12 weeks of alcohol feeding, with no significant effects at earlier time points. This was associated, at 12 weeks, with significantly decreased liver hepcidin expression and serum hepcidin levels. Protein expressions of duodenal ferroportin (at 8 and 12 weeks) and divalent metal transporter 1 (at 8 weeks) were increased. Serum Fe levels rose progressively to significantly higher levels at 12 weeks. Histopathological examination of the liver showed mild steatosis, but no stainable Fe in mice fed alcohol for up to 12 weeks. In summary, alcohol ingestion by mice in this study affected several Fe-related parameters, but produced no hepatic Fe accumulation. On the contrary, alcohol-induced decreases in hepatic Fe levels were seen and may contribute to alcohol-induced suppression of hepcidin.

scholarly journals Divalent Metal Transporter 1 Knock-Down Modulates IL-1β Mediated Pancreatic Beta-Cell Pro-Apoptotic Signaling Pathways through the Autophagic Machinery

2021 ◽  
Vol 22 (15) ◽  
pp. 8013
Author(s):  
Taewook Kang ◽  
Honggang Huang ◽  
Thomas Mandrup-Poulsen ◽  
Martin R. Larsen
Keyword(s):  
Cell Death ◽  
Divalent Metal ◽  
Β Cells ◽  
Β Cell ◽  
Divalent Metal Transporter 1 ◽  
Divalent Metal Transporter ◽  
Knock Down ◽  
Metal Transporter ◽  
Cell Functions ◽  
Protective Proteins

Pro-inflammatory cytokines promote cellular iron-import through enhanced divalent metal transporter-1 (DMT1) expression in pancreatic β-cells, consequently cell death. Inhibition of β-cell iron-import by DMT1 silencing protects against apoptosis in animal models of diabetes. However, how alterations of signaling networks contribute to the protective action of DMT1 knock-down is unknown. Here, we performed phosphoproteomics using our sequential enrichment strategy of mRNA, protein, and phosphopeptides, which enabled us to explore the concurrent molecular events in the same set of wildtype and DMT1-silenced β-cells during IL-1β exposure. Our findings reveal new phosphosites in the IL-1β-induced proteins that are clearly reverted by DMT1 silencing towards their steady-state levels. We validated the levels of five novel phosphosites of the potential protective proteins using parallel reaction monitoring. We also confirmed the inactivation of autophagic flux that may be relevant for cell survival induced by DMT1 silencing during IL-1β exposure. Additionally, the potential protective proteins induced by DMT1 silencing were related to insulin secretion that may lead to improving β-cell functions upon exposure to IL-1β. This global profiling has shed light on the signal transduction pathways driving the protection against inflammation-induced cell death in β-cells after DMT1 silencing.

Does divalent metal transporter 1 mediate the intestinal absorption of arsenic?

2014 ◽  
Vol 229 ◽  
pp. S88
Author(s):  
Zeliha Kayaalti ◽  
Dilek Kaya Akyuzlu ◽  
Vugar Ali Türksoy ◽  
Esma Soylemez ◽  
Tulin Soylemezoglu
Keyword(s):  
Intestinal Absorption ◽  
Divalent Metal ◽  
Divalent Metal Transporter 1 ◽  
Divalent Metal Transporter ◽  
Metal Transporter

Copper repletion enhances apical iron uptake and transepithelial iron transport by Caco-2 cells

2002 ◽  
Vol 282 (3) ◽  
pp. G527-G533 ◽  
Author(s):  
Okhee Han ◽  
Marianne Wessling-Resnick
Keyword(s):  
Iron Uptake ◽  
Iron Transport ◽  
Cell Monolayer ◽  
Transepithelial Transport ◽  
Apical Surface ◽  
Divalent Metal Transporter 1 ◽  
Divalent Metal Transporter ◽  
Metal Transporter ◽  
Copper Status ◽  
Copper Supplementation

The influence of copper status on Caco-2 cell apical iron uptake and transepithelial transport was examined. Cells grown for 7–8 days in media supplemented with 1 μM CuCl2had 10-fold higher cellular levels of copper compared with control. Copper supplementation did not affect the integrity of differentiated Caco-2 cell monolayers grown on microporous membranes. Copper-repleted cells displayed increased uptake of iron as well as increased transport of iron across the cell monolayer. Northern blot analysis revealed that expression of the apical iron transporter divalent metal transporter-1 (DMT1), the basolateral transporter ferroportin-1 (Fpn1), and the putative ferroxidase hephaestin (Heph) was upregulated by copper supplementation, whereas the recently identified ferrireductase duodenal cytochrome b (Dcytb) was not. These results suggest that DMT1, Fpn1, and Heph are involved in the iron uptake process modulated by copper status. Although a clear role for Dcytb was not identified, an apical surface ferrireductase was modulated by copper status, suggesting that its function also contributes to the enhanced iron uptake by copper-repleted cells. A model is proposed wherein copper promotes iron depletion of intestinal Caco-2 cells, creating a deficiency state that induces upregulation of iron transport factors.

scholarly journals The Divalent Metal Transporter 1 (DMT1) Is Required for Iron Uptake and Normal Development of Oligodendrocyte Progenitor Cells

2018 ◽  
Vol 38 (43) ◽  
pp. 9142-9159 ◽  
Author(s):  
Veronica T. Cheli ◽  
Diara A. Santiago González ◽  
Leandro N. Marziali ◽  
Norma N. Zamora ◽  
María E. Guitart ◽  
...  
Keyword(s):  
Progenitor Cells ◽  
Iron Uptake ◽  
Normal Development ◽  
Divalent Metal ◽  
Oligodendrocyte Progenitor Cells ◽  
Divalent Metal Transporter 1 ◽  
Oligodendrocyte Progenitor ◽  
Divalent Metal Transporter ◽  
Metal Transporter

scholarly journals Hyperglycemia Does Not Affect Iron Mediated Toxicity of Cultured Endothelial and Renal Tubular Epithelial Cells: Influence of L-Carnosine

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Shiqi Zhang ◽  
Emmanouil Ntasis ◽  
Sarah Kabtni ◽  
Jaap van den Born ◽  
Gerjan Navis ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Umbilical Vein ◽  
Receptor Protein ◽  
Dependent Manner ◽  
Tubular Epithelial Cells ◽  
Intracellular Iron ◽  
Alternative Source ◽  
Divalent Metal Transporter 1 ◽  
Divalent Metal Transporter ◽  
Metal Transporter

Iron has been suggested to affect the clinical course of type 2 diabetes (T2DM) as accompanying increased intracellular iron accumulation may provide an alternative source for reactive oxygen species (ROS). Although carnosine has proven its therapeutic efficacy in rodent models of T2DM, little is known about its efficacy to protect cells from iron toxicity. We sought to assess if high glucose (HG) exposure makes cultured human umbilical vein endothelial cells (HUVECs) and renal proximal tubular epithelial cells (PTECs) more susceptible to metal induced toxicity and if this is ameliorated by L-carnosine. HUVECs and PTECs, cultured under normal glucose (5 mM, NG) or HG (30 mM), were challenged for 24 h with FeCl3. Cell viability was not impaired under HG conditions nor did HG increase susceptibility to FeCl3. HG did not change the expression of divalent metal transporter 1 (DMT1), ferroportin (IREG), and transferrin receptor protein 1 (TFRC). Irrespective of glucose concentrations L-carnosine prevented toxicity in a dose-dependent manner, only if it was present during the FeCl3challenge. Hence our study indicates that iron induced cytotoxicity is not enhanced under HG conditions. L-Carnosine displayed a strong protective effect, most likely by chelation of iron mediated toxicity.

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