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Płonka D, Wiśniewska MD, Ziemska-Legięcka J, Grynberg M, Bal W. The Cu(II) affinity constant and reactivity of Hepcidin-25, the main iron regulator in human blood. J Inorg Biochem 2023; 248:112364. [PMID: 37689037 DOI: 10.1016/j.jinorgbio.2023.112364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/21/2023] [Accepted: 09/01/2023] [Indexed: 09/11/2023]
Abstract
Hepcidin is an iron regulatory hormone that does not bind iron directly. Instead, its mature 25-peptide form (H25) contains a binding site for other metals, the so-called ATCUN/NTS (amino-terminal Cu/Ni binding site). The Cu(II)-hepcidin complex was previously studied, but due to poor solubility and difficult handling of the peptide the definitive account on the binding equilibrium was not obtained reliably. In this study we performed a series of fluorescence competition experiments between H25 and its model peptides containing the same ATCUN/NTS site and determined the Cu(II) conditional binding constant of the CuH25 complex at pH 7.4, CK7.4 = 4 ± 2 × 1014 M-1. This complex was found to be very inert in exchange reactions and poorly reactive in the ascorbate consumption test. The consequences of these findings for the putative role of Cu(II) interactions with H25 are discussed.
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Affiliation(s)
- Dawid Płonka
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, Warsaw 02-106, Poland
| | - Marta D Wiśniewska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, Warsaw 02-106, Poland
| | - Joanna Ziemska-Legięcka
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, Warsaw 02-106, Poland
| | - Marcin Grynberg
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, Warsaw 02-106, Poland
| | - Wojciech Bal
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, Warsaw 02-106, Poland.
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2
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Zhang X, Zhou J, Holbein BE, Lehmann C. Iron Chelation as a Potential Therapeutic Approach in Acute Lung Injury. Life (Basel) 2023; 13:1659. [PMID: 37629516 PMCID: PMC10455621 DOI: 10.3390/life13081659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/28/2023] [Accepted: 07/29/2023] [Indexed: 08/27/2023] Open
Abstract
Acute lung injury (ALI) has been challenging health care systems since before the COVID-19 pandemic due to its morbidity, mortality, and length of hospital stay. In view of the complex pathogenesis of ALI, effective strategies for its prevention and treatment are still lacking. A growing body of evidence suggests that iron dysregulation is a common characteristic in many subtypes of ALI. On the one hand, iron is needed to produce reactive oxygen species (ROS) as part of the immune response to an infection; on the other hand, iron can accelerate the occurrence of ferroptosis and extend host cell damage. Iron chelation represents a novel therapeutic strategy for alleviating lung injury and improving the survival of patients with ALI. This article reviews the current knowledge of iron homeostasis, the role of iron in ALI development, and potential therapeutic targets.
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Affiliation(s)
- Xiyang Zhang
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, NS B3H 1X5, Canada; (X.Z.); (J.Z.)
- Department of Anesthesiology, Nanfang Hospital, Southern Medical University, 510515 Guangzhou, China
| | - Juan Zhou
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, NS B3H 1X5, Canada; (X.Z.); (J.Z.)
| | - Bruce E. Holbein
- Department of Microbiology & Immunology, Dalhousie University, Halifax, NS B3H 1X5, Canada;
| | - Christian Lehmann
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, NS B3H 1X5, Canada; (X.Z.); (J.Z.)
- Department of Microbiology & Immunology, Dalhousie University, Halifax, NS B3H 1X5, Canada;
- Department of Physiology & Biophysics, Dalhousie University, Halifax, NS B3H 1X5, Canada
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada
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3
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Abbasi U, Abbina S, Gill A, Takuechi LE, Kizhakkedathu JN. Role of Iron in the Molecular Pathogenesis of Diseases and Therapeutic Opportunities. ACS Chem Biol 2021; 16:945-972. [PMID: 34102834 DOI: 10.1021/acschembio.1c00122] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Iron is an essential mineral that serves as a prosthetic group for a variety of proteins involved in vital cellular processes. The iron economy within humans is highly conserved in that there is no proper iron excretion pathway. Therefore, iron homeostasis is highly evolved to coordinate iron acquisition, storage, transport, and recycling efficiently. A disturbance in this state can result in excess iron burden in which an ensuing iron-mediated generation of reactive oxygen species imparts widespread oxidative damage to proteins, lipids, and DNA. On the contrary, problems in iron deficiency either due to genetic or nutritional causes can lead to a number of iron deficiency disorders. Iron chelation strategies have been in the works since the early 1900s, and they still remain the most viable therapeutic approach to mitigate the toxic side effects of excess iron. Intense investigations on improving the efficacy of chelation strategies while being well tolerated and accepted by patients have been a particular focus for many researchers over the past 30 years. Moreover, recent advances in our understanding on the role of iron in the pathogenesis of different diseases (both in iron overload and iron deficiency conditions) motivate the need to develop new therapeutics. We summarized recent investigations into the role of iron in health and disease conditions, iron chelation, and iron delivery strategies. Information regarding small molecule as well as macromolecular approaches and how they are employed within different disease pathogenesis such as primary and secondary iron overload diseases, cancer, diabetes, neurodegenerative diseases, infections, and in iron deficiency is provided.
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Affiliation(s)
- Usama Abbasi
- Centre for Blood Research, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
- Department of Pathology and Laboratory Medicine, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z7
| | - Srinivas Abbina
- Centre for Blood Research, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
- Department of Pathology and Laboratory Medicine, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z7
| | - Arshdeep Gill
- Centre for Blood Research, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
| | - Lily E. Takuechi
- Centre for Blood Research, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
- Department of Pathology and Laboratory Medicine, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z7
| | - Jayachandran N. Kizhakkedathu
- Centre for Blood Research, Life Sciences Institute, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
- Department of Pathology and Laboratory Medicine, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z7
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
- The School of Biomedical Engineering, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
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4
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Diepeveen LE, Laarakkers CM, Peters HPE, van Herwaarden AE, Groenewoud H, IntHout J, Wetzels JF, van Swelm RPL, Swinkels DW. Unraveling Hepcidin Plasma Protein Binding: Evidence from Peritoneal Equilibration Testing. Pharmaceuticals (Basel) 2019; 12:ph12030123. [PMID: 31450766 PMCID: PMC6789442 DOI: 10.3390/ph12030123] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/05/2019] [Accepted: 08/14/2019] [Indexed: 12/21/2022] Open
Abstract
Peptide hormone hepcidin regulates systemic iron metabolism and has been described to be partially bound to α2-macroglobulin and albumin in blood. However, the reported degree of hepcidin protein binding varies between <3% and ≈89%. Since protein-binding may influence hormone function and quantification, better insight into the degree of hepcidin protein binding is essential to fully understand the biological behavior of hepcidin and interpretation of its measurement in patients. Here, we used peritoneal dialysis to assess human hepcidin protein binding in a functional human setting for the first time. We measured freely circulating solutes in blood and peritoneal fluid of 14 patients with end-stage renal disease undergoing a peritoneal equilibration test to establish a curve describing the relation between molecular weight and peritoneal clearance. Calculated binding percentages of total cortisol and testosterone confirmed our model. The protein-bound fraction of hepcidin was calculated to be 40% (±23%). We, therefore, conclude that a substantial proportion of hepcidin is freely circulating. Although a large inter-individual variation in hepcidin clearance, besides patient-specific peritoneal transport characteristics, may have affected the accuracy of the determined binding percentage, we describe an important step towards unraveling human hepcidin plasma protein binding in vivo including the caveats that need further research.
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Affiliation(s)
- Laura E Diepeveen
- Department of Laboratory Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands.
| | - Coby M Laarakkers
- Department of Laboratory Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands
| | - Hilde P E Peters
- Department of Nephrology, Isala Hospital, 8025 Zwolle, The Netherlands
| | - Antonius E van Herwaarden
- Department of Laboratory Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands
| | - Hans Groenewoud
- Department of Health Evidence, Radboud University Medical Center, 6525 Nijmegen, The Netherlands
| | - Joanna IntHout
- Department of Health Evidence, Radboud University Medical Center, 6525 Nijmegen, The Netherlands
| | - Jack F Wetzels
- Department of Nephrology, Radboud University Medical Center, 6525 Nijmegen, The Netherlands
| | - Rachel P L van Swelm
- Department of Laboratory Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands
| | - Dorine W Swinkels
- Department of Laboratory Medicine, Radboud University Medical Center, 6525 Nijmegen, The Netherlands
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Luo T, Lei L, Chen F, Zheng S, Deng Z. Iron homeostasis in the human body and nutritional iron deficiency and solutions in China. J Food Biochem 2018. [DOI: 10.1111/jfbc.12673] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Ting Luo
- State Key Laboratory of Food Science and Technology Nanchang University Nanchang China
| | - Lin Lei
- College of Food Science Southwest University Chongqing China
| | - Fang Chen
- School of Public Health Nanchang University Nanchang China
- Jiangxi Provincial Key Laboratory of Prevention Medicine Nanchang University Nanchang China
| | - Shilian Zheng
- State Key Laboratory of Food Science and Technology Nanchang University Nanchang China
| | - Ze‐yuan Deng
- State Key Laboratory of Food Science and Technology Nanchang University Nanchang China
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6
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Stoffel NU, Zeder C, Fort E, Swinkels DW, Zimmermann MB, Moretti D. Prediction of human iron bioavailability using rapid c-ELISAs for human plasma hepcidin. Clin Chem Lab Med 2017. [PMID: 28628474 DOI: 10.1515/cclm-2017-0097] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Hepcidin is the central systemic regulator of iron metabolism, but its quantification in biological fluids is challenging. Rapid, accurate and user-friendly methods are needed. Our aim was to assess the ability of hepcidin as measured by three different c-ELISA assays to predict iron bioavailability in humans. METHODS The three assays used were commercially available DRG and Peninsula assays and the c-ELISA method performed at Radboud University Medical Centre, Nijmegen, The Netherlands (Hepcidinanalysis.com), validated by comparative measurements with time-of-flight mass spectrometry. We analyzed plasma samples (n=37) selected to represent a broad range of hepcidin concentrations from a subgroup of healthy, iron-depleted women in a study assessing fractional absorption from iron supplements. RESULTS In single regressions, all three c-ELISA assays were predictors of fractional iron absorption: R2=0.363 (DRG), R2=0.281 (Peninsula) and R2=0.327 (Hepcidinanalysis.com). In multiple regressions, models including hepcidin measured with either DRG-, Peninsula or Hepcidinanalysis.com explained 55.7%, 44.5% and 52.5% of variance in fractional absorption, and hepcidin was a strong predictor of fractional absorption irrespective of the hepcidin assays used. However, we found significant differences in absolute values for hepcidin between different methods. Both the DRG assay's (y=0.61x+0.87; R2=0.873) and the Peninsula assay's measurements (y=1.88x+0.62; R2=0.770) were correlated with Hepcidinanalysis.com. CONCLUSIONS The biological variability in plasma hepcidin, (inter-sample CV) was 5-10-fold higher for both the Peninsula and DRG assay than the analytical variably (inter-run within-sample CV) suggesting substantial discriminatory power to distinguish biological hepcidin variation. Between methods, prediction of iron bioavailability in generally healthy iron depleted subjects appears comparable.
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Expression of hepcidin and ferroportin in full term placenta of pregnant cows. Theriogenology 2017; 103:90-97. [PMID: 28780484 DOI: 10.1016/j.theriogenology.2017.07.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/04/2017] [Accepted: 07/25/2017] [Indexed: 12/29/2022]
Abstract
Hepcidin (HEP) and ferroportin (FPN) play a central role in systemic iron homeostasis. The HEP/FPN axis controls both extracellular iron concentration and total body iron levels. HEP is synthesized mainly by hepatocytes and controls the absorption of dietary iron and the distribution of iron to the various cell types; its synthesis is regulated by both iron and innate immunity. FPN is a membrane protein and the major exporter of iron from mammalian cells, including iron recycling macrophages, iron absorbing duodenal enterocytes, and iron storing hepatocytes. HEP limits the pool of extracellular iron by binding FPN and mediating its degradation, thus preventing its release from intracellular sources. Here we investigated, for the first time, the molecular and morphological expression of HEP and FPN in placenta of pregnant cows at term. Their expression has been evaluated investigating their mRNAs by reverse transcriptase PCR (RT-PCR). Sequencing of related amplicons revealed a 100% identity with HEP and FPN sequences from Bos taurus as reported in the GeneBank (mRNASequence ID: NM_001114508.2 and ID: NM_001077970.1, respectively). HEP and FPN proteins have also been revealed by Western blot analysis and immunohistochemistry. The strongest immunoreactivity for both proteins was observed in the cytoplasm of the trophoblastic cells of the villi and the caruncular crypts of the placentome. Hep mRNA was more representative in caruncular rather cotyledonar areas; on the contrary, Fpn mRNA was more expressed in cotyledonar rather than in caruncular areas. Transcripts of ferritin, transferrin and its receptor have been also documented by real time RT-PCR. HEP and FPN placental proteins may play a dual role. HEP/FPN axis seems to have a central role in infections, with microorganisms within macrophages or that survive in the bloodstream or other cellular spaces. In addition, HEP may be responsible for iron flux regulation as a molecular bridge for iron trafficking and response to infection. FPN may also have a significant role for embryonic development, growth and organogenesis.
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8
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Measurement of hepcidin isoforms in human serum by liquid chromatography with high resolution mass spectrometry. Bioanalysis 2017; 9:541-553. [DOI: 10.4155/bio-2016-0286] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Aim: Hepcidin-25 is the master regulator of iron homeostasis. N-truncated isoforms of hepcidin-25 have been identified (hepcidin-20, -22, -24), although data on the concentrations of these isoforms are sparse. Materials & methods: Serum was mixed with aqueous formic acid, and the supernatant loaded onto a 96-well-SPE-plate. Eluted analytes were analyzed using LC–HR-MS. Forty-seven paired dipotassium-EDTA human plasma and serum samples were analyzed. Results: The LLOQ was 1 μg/l (all analytes). Accuracy and precision were acceptable. There was a good correlation (R2 >0.90, all analytes) between matrices. The median (range) serum hepcidin-20, -22, -24 and -25 concentrations measured were 4 (1–40), 8 (2–20), 8 (1–50) and 39 (1–334) μg/l, respectively. Conclusion: LC–HR-MS is widely applicable to the measurement of hepcidin-25, and truncated isoforms.
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9
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Vyoral D, Jiri Petrak. Therapeutic potential of hepcidin − the master regulator of iron metabolism. Pharmacol Res 2017; 115:242-254. [DOI: 10.1016/j.phrs.2016.11.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/03/2016] [Accepted: 11/07/2016] [Indexed: 12/14/2022]
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10
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Relationship between the Ingestion of a Polyphenol-Rich Drink, Hepcidin Hormone, and Long-Term Training. Molecules 2016; 21:molecules21101333. [PMID: 27740603 PMCID: PMC6273972 DOI: 10.3390/molecules21101333] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 09/28/2016] [Accepted: 10/01/2016] [Indexed: 12/21/2022] Open
Abstract
The effects of polyphenol-rich foods on the iron status of athletes, as well as the effect of physical training on the hormone hepcidin, implicated in iron metabolism, are not clear. We investigated the influence on iron metabolism of a long-term training intervention of 120 days, measuring the hepcidin concentration in the plasma of 16 elite triathletes, and the effect of the ingestion of 200 mL of either aronia-citrus juice or a placebo drink for 45 days, in a crossover design. The highest plasma hepcidin concentrations were observed at the beginning of the study (116 ± 63 nM) and levels steadily decreased until the end of the intervention (final value 10 ± 7.5 nM). Long-term training might reduce inflammation and, hence, could be responsible for the decrease in hepcidin in triathletes. Polyphenols from aronia-citrus juice did not interfere in iron absorption, as we did not observe significant differences between the intake of the placebo drink or juice with regard to hepcidin levels. Further studies are required to ascertain the time and conditions necessary to restore hepcidin levels, which reflect the iron status of triathletes.
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van der Vorm LN, Hendriks JCM, Laarakkers CM, Klaver S, Armitage AE, Bamberg A, Geurts-Moespot AJ, Girelli D, Herkert M, Itkonen O, Konrad RJ, Tomosugi N, Westerman M, Bansal SS, Campostrini N, Drakesmith H, Fillet M, Olbina G, Pasricha SR, Pitts KR, Sloan JH, Tagliaro F, Weykamp CW, Swinkels DW. Toward Worldwide Hepcidin Assay Harmonization: Identification of a Commutable Secondary Reference Material. Clin Chem 2016; 62:993-1001. [DOI: 10.1373/clinchem.2016.256768] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 04/07/2016] [Indexed: 11/06/2022]
Abstract
Abstract
BACKGROUND
Absolute plasma hepcidin concentrations measured by various procedures differ substantially, complicating interpretation of results and rendering reference intervals method dependent. We investigated the degree of equivalence achievable by harmonization and the identification of a commutable secondary reference material to accomplish this goal.
METHODS
We applied technical procedures to achieve harmonization developed by the Consortium for Harmonization of Clinical Laboratory Results. Eleven plasma hepcidin measurement procedures (5 mass spectrometry based and 6 immunochemical based) quantified native individual plasma samples (n = 32) and native plasma pools (n = 8) to assess analytical performance and current and achievable equivalence. In addition, 8 types of candidate reference materials (3 concentrations each, n = 24) were assessed for their suitability, most notably in terms of commutability, to serve as secondary reference material.
RESULTS
Absolute hepcidin values and reproducibility (intrameasurement procedure CVs 2.9%–8.7%) differed substantially between measurement procedures, but all were linear and correlated well. The current equivalence (intermeasurement procedure CV 28.6%) between the methods was mainly attributable to differences in calibration and could thus be improved by harmonization with a common calibrator. Linear regression analysis and standardized residuals showed that a candidate reference material consisting of native lyophilized plasma with cryolyoprotectant was commutable for all measurement procedures. Mathematically simulated harmonization with this calibrator resulted in a maximum achievable equivalence of 7.7%.
CONCLUSIONS
The secondary reference material identified in this study has the potential to substantially improve equivalence between hepcidin measurement procedures and contributes to the establishment of a traceability chain that will ultimately allow standardization of hepcidin measurement results.
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Affiliation(s)
| | - Jan C M Hendriks
- Department of Health Evidence, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Coby M Laarakkers
- Department of Laboratory Medicine and
- Hepcidinanalysis.com, Nijmegen, the Netherlands
| | | | - Andrew E Armitage
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK, and Blood Theme, NIHR Oxford Biomedical Research Centre, Oxford, UK
| | | | | | | | | | - Outi Itkonen
- Helsinki University Central Hospital, Laboratory Division HUSLAB, Helsinki, Finland
| | | | - Naohisa Tomosugi
- Division of Advanced Medicine, Medical Research Institute, Kanazawa Medical University, Ishikawa, Japan
| | | | | | | | - Hal Drakesmith
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK, and Blood Theme, NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Marianne Fillet
- Department of Analytical Pharmaceutical Chemistry, Institute of Pharmacy, University of Liège, Liège, Belgium
| | | | - Sant-Rayn Pasricha
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK, and Blood Theme, NIHR Oxford Biomedical Research Centre, Oxford, UK
| | | | | | - Franco Tagliaro
- Department of Diagnostics and Public Health, University of Verona, Italy
| | - Cas W Weykamp
- Department of Clinical Chemistry, Queen Beatrix Hospital, Winterswijk, the Netherlands
| | - Dorine W Swinkels
- Department of Laboratory Medicine and
- Hepcidinanalysis.com, Nijmegen, the Netherlands
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Abstract
The discovery of the iron-regulatory hormone hepcidin in 2001 has revolutionized our understanding of iron disorders, and its measurement should advance diagnosis/treatment of these conditions. Although several assays have been developed, a gold standard is still lacking, and efforts toward harmonization are ongoing. Nevertheless, promising applications can already be glimpsed, ranging from the use of hepcidin levels for diagnosing iron-refractory iron deficiency anemia to global health applications such as guiding safe iron supplementation in developing countries with high infection burden.
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Abstract
Anaemia affects roughly a third of the world's population; half the cases are due to iron deficiency. It is a major and global public health problem that affects maternal and child mortality, physical performance, and referral to health-care professionals. Children aged 0-5 years, women of childbearing age, and pregnant women are particularly at risk. Several chronic diseases are frequently associated with iron deficiency anaemia--notably chronic kidney disease, chronic heart failure, cancer, and inflammatory bowel disease. Measurement of serum ferritin, transferrin saturation, serum soluble transferrin receptors, and the serum soluble transferrin receptors-ferritin index are more accurate than classic red cell indices in the diagnosis of iron deficiency anaemia. In addition to the search for and treatment of the cause of iron deficiency, treatment strategies encompass prevention, including food fortification and iron supplementation. Oral iron is usually recommended as first-line therapy, but the most recent intravenous iron formulations, which have been available for nearly a decade, seem to replenish iron stores safely and effectively. Hepcidin has a key role in iron homoeostasis and could be a future diagnostic and therapeutic target. In this Seminar, we discuss the clinical presentation, epidemiology, pathophysiology, diagnosis, and acute management of iron deficiency anaemia, and outstanding research questions for treatment.
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Affiliation(s)
- Anthony Lopez
- Department of Hepato-Gastroenterology and Inserm U954, University Hospital of Nancy, Lorraine University, Vandoeuvre-lès-Nancy, France
| | - Patrice Cacoub
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7211, Paris, France; Inflammation-Immunopathology-Biotherapy Department, F-75005, Paris, France; AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Department of Internal Medicine and Clinical Immunology, F-75013, Paris, France
| | | | - Laurent Peyrin-Biroulet
- Department of Hepato-Gastroenterology and Inserm U954, University Hospital of Nancy, Lorraine University, Vandoeuvre-lès-Nancy, France.
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14
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van Swelm RPL, Wetzels JFM, Verweij VGM, Laarakkers CMM, Pertijs JCLM, van der Wijst J, Thévenod F, Masereeuw R, Swinkels DW. Renal Handling of Circulating and Renal-Synthesized Hepcidin and Its Protective Effects against Hemoglobin-Mediated Kidney Injury. J Am Soc Nephrol 2016; 27:2720-32. [PMID: 26825531 DOI: 10.1681/asn.2015040461] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 12/12/2015] [Indexed: 11/03/2022] Open
Abstract
Urinary hepcidin may have protective effects against AKI. However, renal handling and the potential protective mechanisms of hepcidin are not fully understood. By measuring hepcidin levels in plasma and urine using mass spectrometry and the kidney using immunohistochemistry after intraperitoneal administration of human hepcidin-25 (hhep25) in C57Bl/6N mice, we showed that circulating hepcidin is filtered by the glomerulus and degraded to smaller isoforms detected in urine but not plasma. Moreover, hepcidin colocalized with the endocytic receptor megalin in proximal tubules, and compared with wild-type mice, megalin-deficient mice showed higher urinary excretion of injected hhep25 and no hepcidin staining in proximal tubules that lack megalin. This indicates that hepcidin is reaborbed in the proximal tubules by megalin dependent endocytosis. Administration of hhep25 concomitant with or 4 hours after a single intravenous dose of hemoglobin abolished hemoglobin-induced upregulation of urinary kidney injury markers (NGAL and KIM-1) and renal Interleukin-6 and Ngal mRNA observed 24 hours after administration but did not affect renal ferroportin expression at this point. Notably, coadministration of hhep25 and hemoglobin but not administration of either alone greatly increased renal mRNA expression of hepcidin-encoding Hamp1 and hepcidin staining in distal tubules. These findings suggest a role for locally synthesized hepcidin in renal protection. Our observations did not support a role for ferroportin in hhep25-mediated protection against hemoglobin-induced early injury, but other mechanisms of cellular iron handling may be involved. In conclusion, our data suggest that both systemically delivered and locally produced hepcidin protect against hemoglobin-induced AKI.
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Affiliation(s)
| | | | | | | | | | | | - Frank Thévenod
- Institute of Physiology, Pathophysiology and Toxicology, Center for Biomedical Training and Research, University of Witten/Herdecke, Witten, Germany; and
| | - Rosalinde Masereeuw
- Pharmacology and Toxicology, Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht, The Netherlands
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15
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Theurl M, Song D, Clark E, Sterling J, Grieco S, Altamura S, Galy B, Hentze M, Muckenthaler MU, Dunaief JL. Mice with hepcidin-resistant ferroportin accumulate iron in the retina. FASEB J 2015; 30:813-23. [PMID: 26506980 DOI: 10.1096/fj.15-276758] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 10/13/2015] [Indexed: 12/13/2022]
Abstract
Because ferroportin (Fpn) is the only known mammalian cellular iron exporter, understanding its localization and regulation within the retina would shed light on the direction of retinal iron flux. The hormone hepcidin may regulate retinal Fpn, as it triggers Fpn degradation in the gut. Immunofluorescence was used to label Fpn in retinas of mice with 4 different genotypes (wild type; Fpn C326S, a hepcidin-resistant Fpn; hepcidin knockout; and ceruloplasmin/hephaestin double knockout). No significant difference in Fpn levels was observed in these retinas. Fpn localized to the abluminal side of the outer plexiform vascular endothelial cells, Müller glia cells, and the basolateral side of the retinal pigment epithelium. Adeno-associated virus (AAV)-hepcidin was injected into the eyes of hepcidin knockout mice, while AAV-lacZ was injected into the contralateral eyes as a control. AAV-hepcidin injected eyes had increased ferritin immunolabeling in retinal vascular endothelial cells. Fpn C326S mice had systemic iron overload compared to wild type and had the fastest retinal iron accumulation of any hereditary model studied to date. The results suggest that physiologic hepcidin levels are insufficient to alter Fpn levels within the retinal pigment epithelium and Müller cells, but may limit iron transport into the retina from vascular endothelial cells.
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Affiliation(s)
- Milan Theurl
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Delu Song
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Esther Clark
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Jacob Sterling
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Steve Grieco
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Sandro Altamura
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Bruno Galy
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Matthias Hentze
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Martina U Muckenthaler
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
| | - Joshua L Dunaief
- *F. M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Ophthalmology and Optometry, Innsbruck Medical University, Innsbruck, Austria; Department of Psychiatry and Behavioral Sciences, and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA; Department of Pediatric Hematology, Oncology, and Immunology, University of Heidelberg, Heidelberg, Germany; Molecular Medicine Partnership Unit, Heidelberg, Germany; and European Molecular Biology Laboratory, Heidelberg, Germany
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Validation of hepcidin quantification in plasma using LC-HRMS and discovery of a new hepcidin isoform. Bioanalysis 2014; 5:2509-20. [PMID: 24138624 DOI: 10.4155/bio.13.225] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Hepcidin, a 25 amino acid peptide, plays an important role in iron homeostasis. Some hepcidin truncated peptides have antibiotic effects. RESULTS A new analytical method for hepcidin determination in human plasma using LC-HRMS operating in full-scan acquisition mode has been validated. The extraction consists of protein precipitation and a drying reconstitution step; a 2.1 x 50 mm (idxL) C18 analytical column was used. Detection specificity, stability, accuracy, precision and recoveries were determined. The LOQ/LOD were 0.25/0.1 nM, respectively. More than 600 injections of plasma extracts were performed, allowing evaluation of the assay robustness. Hepcidin-20, hepcidin-22 and a new isoform, hepcidin-24, were detected in patients. CONCLUSION The data underscore the usefulness of LC-HRMS for in-depth investigations related to hepcidin levels and pathways.
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Abstract
The iron hormone hepcidin and its receptor and cellular iron exporter ferroportin control the major fluxes of iron into blood plasma: intestinal iron absorption, the delivery of recycled iron from macrophages, and the release of stored iron from hepatocytes. Because iron losses are comparatively very small, iron absorption and its regulation by hepcidin and ferroportin determine total body iron content. Hepcidin is in turn feedback-regulated by plasma iron concentration and iron stores, and negatively regulated by the activity of erythrocyte precursors, the dominant consumers of iron. Hepcidin and ferroportin also play a role in host defense and inflammation, and hepcidin synthesis is induced by inflammatory signals including interleukin-6 and activin B. This review summarizes and discusses recent progress in molecular characterization of systemic iron homeostasis and its disorders, and identifies areas for further investigation.
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Abstract
Iron is a micronutrient essential for almost all organisms: bacteria, plants, and animals. It is a metal that exists in multiple redox states, including the divalent ferrous (Fe(2+)) and the trivalent ferric (Fe(3+)) species. The multiple oxidation states of iron make it excellent for electron transfer, allowing iron to be selected during evolution as a cofactor for many proteins involved in central cellular processes including oxygen transport, mitochondrial respiration, and DNA synthesis. However, the redox cycling of ferrous and ferric iron in the presence of H2O2, which is physiologically present in the cells, also leads to the production of free radicals (Fenton reaction) that can attack and damage lipids, proteins, DNA, and other cellular components. To meet the physiological needs of the body, but to prevent cellular damage by iron, the amount of iron in the body must be tightly regulated. Here we review how the liver is the central conductor of systemic iron balance and show that this central role is related to the secretion of a peptide hormone hepcidin by hepatocytes. We then review how the liver receives and integrates the many signals that report the body's iron needs to orchestrate hepcidin production and maintain systemic iron homeostasis.
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The removal of serum hepcidin by different dialysis membranes. Int J Artif Organs 2013; 36:633-9. [PMID: 23918276 DOI: 10.5301/ijao.5000221] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2013] [Indexed: 12/16/2022]
Abstract
PURPOSE Hepcidin has been suspected to be associated with anemia of chronic disease, which is commonly observed in patients with maintenance hemodialysis (MHD). As almost of hepcidin is bounded to protein, it is essential to clarify which kind of dialysis membrane can remove it efficiently. METHODS Ex vivo study: 50 mL of whole blood from healthy volunteers were circulated for 2 h in a microcircuit with mini-dialyzers (acrylonitrile-co-methallyl sulfonate (AN69) or polysulfone (PS)) without ultrafiltration. We measured hepcidin-25 levels at 0, 60, and 120 min in the blood samples. In vivo study: Blood samples were taken from 28 MHD patients at the start and end of HD sessions with PS or AN69. We measured serum levels of hepcidin 20, 22, and 25 by liquid chromatography tandem mass spectrometry, and also measured serum levels of urea nitrogen (UN), β2microglobulin (MG). RESULTS Ex vivo study: Although serum hepcidin 25 levels increased after the ex vivo session with PS, they significantly decreased with AN69. In vivo study: The reduction ratio of β2MG by PS was significantly higher than that of AN69. On the other hand, there was no significant difference in the reduction ratio of hepcidin 20, 22, and 25 between PS and AN69. CONCLUSIONS Both super-flux PS and AN69 similarly removed hepcidin 20 22, and 25. HD with PS might achieve a high removal ratio of hepcidin by enhanced diffusion performance and an increased clearance of small molecule solutes. On the other hand, AN69 might remove hepcidin by adsorption.
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Huang MLH, Austin CJD, Sari MA, Suryo Rahmanto Y, Ponka P, Vyoral D, Richardson DR. Hepcidin bound to α2-macroglobulin reduces ferroportin-1 expression and enhances its activity at reducing serum iron levels. J Biol Chem 2013; 288:25450-25465. [PMID: 23846698 DOI: 10.1074/jbc.m113.471573] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hepcidin regulates iron metabolism by down-regulating ferroportin-1 (Fpn1). We demonstrated that hepcidin is complexed to the blood transport protein, α2-macroglobulin (α2M) (Peslova, G., Petrak, J., Kuzelova, K., Hrdy, I., Halada, P., Kuchel, P. W., Soe-Lin, S., Ponka, P., Sutak, R., Becker, E., Huang, M. L., Suryo Rahmanto, Y., Richardson, D. R., and Vyoral, D. (2009) Blood 113, 6225-6236). However, nothing is known about the mechanism of hepcidin binding to α2M or the effects of the α2M·hepcidin complex in vivo. We show that decreased Fpn1 expression can be mediated by hepcidin bound to native α2M and also, for the first time, hepcidin bound to methylamine-activated α2M (α2M-MA). Passage of high molecular weight α2M·hepcidin or α2M-MA·hepcidin complexes (≈725 kDa) through a Sephadex G-25 size exclusion column retained their ability to decrease Fpn1 expression. Further studies using ultrafiltration indicated that hepcidin binding to α2M and α2M-MA was labile, resulting in some release from the protein, and this may explain its urinary excretion. To determine whether α2M-MA·hepcidin is delivered to cells via the α2M receptor (Lrp1), we assessed α2M uptake and Fpn1 expression in Lrp1(-/-) and Lrp1(+/+) cells. Interestingly, α2M·hepcidin or α2M-MA·hepcidin demonstrated similar activities at decreasing Fpn1 expression in Lrp1(-/-) and Lrp1(+/+) cells, indicating that Lrp1 is not essential for Fpn1 regulation. In vivo, hepcidin bound to α2M or α2M-MA did not affect plasma clearance of α2M/α2M-MA. However, serum iron levels were reduced to a significantly greater extent in mice treated with α2M·hepcidin or α2M-MA·hepcidin relative to unbound hepcidin. This effect could be mediated by the ability of α2M or α2M-MA to retard kidney filtration of bound hepcidin, increasing its half-life. A model is proposed that suggests that unlike proteases, which are irreversibly bound to activated α2M, hepcidin remains labile and available to down-regulate Fpn1.
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Affiliation(s)
- Michael Li-Hsuan Huang
- From the Department of Pathology, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Christopher J D Austin
- From the Department of Pathology, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Marie-Agnès Sari
- the Université Paris Descartes, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, UMR8601 CNRS, 45 Rue des Saints Peres, 75006 Paris, France
| | - Yohan Suryo Rahmanto
- From the Department of Pathology, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Prem Ponka
- the Lady Davis Institute for Medical Research, Montreal, Quebec H3T1E2, Canada
| | - Daniel Vyoral
- the Institute of Hematology and Blood Transfusion, U Nemocnice 1, Prague 2, 128 20, Czech Republic, and; the First Faculty of Medicine, Institute of Pathological Physiology, Charles University in Prague, U Nemocnice 5, Prague 2, 128 53, Czech Republic
| | - Des R Richardson
- From the Department of Pathology, University of Sydney, Sydney, New South Wales 2006, Australia,.
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21
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Preza GC, Pinon R, Ganz T, Nemeth E. Cellular catabolism of the iron-regulatory peptide hormone hepcidin. PLoS One 2013; 8:e58934. [PMID: 23536837 PMCID: PMC3594189 DOI: 10.1371/journal.pone.0058934] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 02/08/2013] [Indexed: 11/18/2022] Open
Abstract
Hepcidin, a 25-amino acid peptide hormone, is the principal regulator of plasma iron concentrations. Hepcidin binding to its receptor, the iron exporter ferroportin, induces ferroportin internalization and degradation, thus blocking iron efflux from cells into plasma. The aim of this study was to characterize the fate of hepcidin after binding to ferroportin. We show that hepcidin is taken up by ferroportin-expressing cells in a temperature- and pH-dependent manner, and degraded together with its receptor. When Texas red-labeled hepcidin (TR-Hep) was added to ferroportin-GFP (Fpn-GFP) expressing cells, confocal microscopy showed co-localization of TR-Hep with Fpn-GFP. Using flow cytometry, we showed that the peptide was almost completely degraded by 24 h after its addition, but that lysosomal inhibitors completely prevented degradation of both ferroportin and hepcidin. In addition, using radio-labeled hepcidin and HPLC analysis we show that hepcidin is not recycled, and that only degradation products are released from the cells. Together these results show that the hormone hepcidin and its receptor ferroportin are internalized together and trafficked to lysosomes where both are degraded.
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Affiliation(s)
- Gloria Cuevas Preza
- Department of Dermatology, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Rogelio Pinon
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California, United States of America
| | - Tomas Ganz
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California, United States of America
- Department of Pathology, David Geffen School of Medicine, University of California, Los Angeles, California, United States of America
| | - Elizabeta Nemeth
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California, United States of America
- * E-mail:
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