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Zhang N, Yang P, Li Y, Ouyang Q, Hou F, Zhu G, Zhang B, Huang J, Jia J, Xu A. Serum Iron Overload Activates the SMAD Pathway and Hepcidin Expression of Hepatocytes via SMURF1. J Clin Transl Hepatol 2024; 12:227-235. [PMID: 38426189 PMCID: PMC10899870 DOI: 10.14218/jcth.2023.00440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 03/02/2024] Open
Abstract
Background and Aims Liver iron overload can induce hepatic expression of bone morphogenic protein (BMP) 6 and activate the BMP/SMAD pathway. However, serum iron overload can also activate SMAD but does not induce BMP6 expression. Therefore, the mechanisms through which serum iron overload activates the BMP/SMAD pathway remain unclear. This study aimed to clarify the role of SMURF1 in serum iron overload and the BMP/SMAD pathway. Methods A cell model of serum iron overload was established by treating hepatocytes with 2 mg/mL of holo-transferrin (Holo-Tf). A serum iron overload mouse model and a liver iron overload mouse model were established by intraperitoneally injecting 10 mg of Holo-Tf into C57BL/6 mice and administering a high-iron diet for 1 week followed by a low-iron diet for 2 days. Western blotting and real-time PCR were performed to evaluate the activation of the BMP/SMAD pathway and the expression of hepcidin. Results Holo-Tf augmented the sensitivity and responsiveness of hepatocytes to BMP6. The E3 ubiquitin-protein ligase SMURF1 mediated Holo-Tf-induced SMAD1/5 activation and hepcidin expression; specifically, SMURF1 expression dramatically decreased when the serum iron concentration was increased. Additionally, the expression of SMURF1 substrates, which are important molecules involved in the transduction of BMP/SMAD signaling, was significantly upregulated. Furthermore, in vivo analyses confirmed that SMURF1 specifically regulated the BMP/SMAD pathway during serum iron overload. Conclusions SMURF1 can specifically regulate the BMP/SMAD pathway by augmenting the responsiveness of hepatocytes to BMPs during serum iron overload.
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Affiliation(s)
- Ning Zhang
- Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Department of Gastroenterology, Beijing Shunyi Hospital, Beijing, China
| | - Pengyao Yang
- Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Yanmeng Li
- Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Qin Ouyang
- Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Fei Hou
- Department of Critical Liver Diseases, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Guixin Zhu
- MOE Key Laboratory of Protein Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Bei Zhang
- Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Jian Huang
- Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Jidong Jia
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Anjian Xu
- Experimental and Translational Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
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Courbon G, Thomas JJ, Martinez-Calle M, Wang X, Spindler J, Von Drasek J, Hunt-Tobey B, Mehta R, Isakova T, Chang W, Creemers JWM, Ji P, Martin A, David V. Bone-derived C-terminal FGF23 cleaved peptides increase iron availability in acute inflammation. Blood 2023; 142:106-118. [PMID: 37053547 PMCID: PMC10356820 DOI: 10.1182/blood.2022018475] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 03/24/2023] [Accepted: 04/06/2023] [Indexed: 04/15/2023] Open
Abstract
Inflammation leads to functional iron deficiency by increasing the expression of the hepatic iron regulatory peptide hepcidin. Inflammation also stimulates fibroblast growth factor 23 (FGF23) production by increasing both Fgf23 transcription and FGF23 cleavage, which paradoxically leads to excess in C-terminal FGF23 peptides (Cter-FGF23), rather than intact FGF23 (iFGF23) hormone. We determined that the major source of Cter-FGF23 is osteocytes and investigated whether Cter-FGF23 peptides play a direct role in the regulation of hepcidin and iron metabolism in response to acute inflammation. Mice harboring an osteocyte-specific deletion of Fgf23 showed a ∼90% reduction in Cter-FGF23 levels during acute inflammation. Reduction in Cter-FGF23 led to a further decrease in circulating iron in inflamed mice owing to excessive hepcidin production. We observed similar results in mice showing impaired FGF23 cleavage owing to osteocyte-specific deletion of Furin. We next showed that Cter-FGF23 peptides bind members of the bone morphogenetic protein (BMP) family, BMP2 and BMP9, which are established inducers of hepcidin. Coadministration of Cter-FGF23 and BMP2 or BMP9 prevented the increase in Hamp messenger RNA and circulating hepcidin levels induced by BMP2/9, resulting in normal serum iron levels. Finally, injection of Cter-FGF23 in inflamed Fgf23KO mice and genetic overexpression of Cter-Fgf23 in wild type mice also resulted in lower hepcidin and higher circulating iron levels. In conclusion, during inflammation, bone is the major source of Cter-FGF23 secretion, and independently of iFGF23, Cter-FGF23 reduces BMP-induced hepcidin secretion in the liver.
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Affiliation(s)
- Guillaume Courbon
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Jane Joy Thomas
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Marta Martinez-Calle
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Xueyan Wang
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Jadeah Spindler
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - John Von Drasek
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Bridget Hunt-Tobey
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Rupal Mehta
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Tamara Isakova
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Wenhan Chang
- Endocrine Research Unit, San Francisco Veterans Affairs Medical Center, University of California San Francisco, San Francisco, CA
| | | | - Peng Ji
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Aline Martin
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Valentin David
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
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3
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Baringer SL, Palsa K, Spiegelman VS, Simpson IA, Connor JR. Apo- and holo-transferrin differentially interact with hephaestin and ferroportin in a novel mechanism of cellular iron release regulation. J Biomed Sci 2023; 30:36. [PMID: 37277838 PMCID: PMC10243088 DOI: 10.1186/s12929-023-00934-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 05/28/2023] [Indexed: 06/07/2023] Open
Abstract
BACKGROUND Apo- (iron free) and holo- (iron bound) transferrin (Tf) participate in precise regulation of brain iron uptake at endothelial cells of the blood-brain barrier. Apo-Tf indicates an iron-deficient environment and stimulates iron release, while holo-Tf indicates an iron sufficient environment and suppresses additional iron release. Free iron is exported through ferroportin, with hephaestin as an aid to the process. Until now, the molecular mechanisms of apo- and holo-Tf influence on iron release was largely unknown. METHODS Here we use a variety of cell culture techniques, including co-immunoprecipitation and proximity ligation assay, in iPSC-derived endothelial cells and HEK 293 cells to investigate the mechanism by which apo- and holo-Tf influence cellular iron release. Given the established role of hepcidin in regulating cellular iron release, we further explored the relationship of hepcidin to transferrin in this model. RESULTS We demonstrate that holo-Tf induces the internalization of ferroportin through the established ferroportin degradation pathway. Furthermore, holo-Tf directly interacts with ferroportin, whereas apo-Tf directly interacts with hephaestin. Only pathophysiological levels of hepcidin disrupt the interaction between holo-Tf and ferroportin, but similar hepcidin levels are unable to interfere with the interaction between apo-Tf and hephaestin. The disruption of the holo-Tf and ferroportin interaction by hepcidin is due to hepcidin's ability to more rapidly internalize ferroportin compared to holo-Tf. CONCLUSIONS These novel findings provide a molecular mechanism for apo- and holo-Tf regulation of iron release from endothelial cells. They further demonstrate how hepcidin impacts these protein-protein interactions, and offer a model for how holo-Tf and hepcidin cooperate to suppress iron release. These results expand on our previous reports on mechanisms mediating regulation of brain iron uptake to provide a more thorough understanding of the regulatory mechanisms mediating cellular iron release in general.
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Affiliation(s)
- Stephanie L Baringer
- Department of Neurosurgery, Penn State College of Medicine, 500 University Drive, Hershey, PA, 17033, USA
| | - Kondaiah Palsa
- Department of Neurosurgery, Penn State College of Medicine, 500 University Drive, Hershey, PA, 17033, USA
| | | | - Ian A Simpson
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA, USA
| | - James R Connor
- Department of Neurosurgery, Penn State College of Medicine, 500 University Drive, Hershey, PA, 17033, USA.
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Abstract
Haemochromatosis is one of the most common genetic diseases affecting patients of northern European ancestry. It is overdiagnosed in patients without iron overload and is underdiagnosed in many patients. Early diagnosis by genetic testing and therapy by periodic phlebotomy can prevent the most serious complications, which include liver cirrhosis, liver cancer, and death. This Seminar includes an update on the origins of haemochromatosis; and an overview pathophysiology, genetics, natural history, signs and symptoms, differential diagnoses, treatment with phlebotomy, outcomes, and future directions.
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Affiliation(s)
- Paul C Adams
- Department of Medicine, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada.
| | - Gary Jeffrey
- Medical School, University of Western Australia, Perth, WA, Australia
| | - John Ryan
- Royal College of Surgeons of Ireland, Dublin, Ireland
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5
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Pistis KD, Westerberg PA, Qureshi AR, Beshara S, Sterner G, Bárány P, Linde T. The effect of high-dose vitamin D supplementation on hepcidin-25 and erythropoiesis in patients with chronic kidney disease. BMC Nephrol 2023; 24:20. [PMID: 36698076 PMCID: PMC9875529 DOI: 10.1186/s12882-022-03014-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 11/21/2022] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Hepcidin is considered to play a central role in the pathophysiology of renal anemia. Recent studies in healthy individuals have demonstrated a suppressive effect of vitamin D (VD) on the expression of hepcidin. In this post-hoc analysis based on a randomized controlled study, we evaluated the effect of supplementing chronic kidney disease (CKD) patients (stage G3-G4) with a high daily dose of native VD on serum levels of hepcidin-25, the hepcidin/ferritin ratio, as well as on markers of erythropoiesis. METHODS Patients with CKD stage G3-G4 included in a double blind, randomized, placebo (PBO) controlled study with available hepcidin measurements were analyzed. Study subjects received either 8000 international units (IU) of cholecalciferol daily or PBO for 12 weeks. We evaluated the change in markers of hepcidin expression, erythropoiesis, and iron status from baseline to week 12 and compared the change between the groups. RESULTS Eighty five patients completed the study. Calcitriol, but not 25-hydroxyvitamin D (25(OH) D), was inversely correlated with serum levels of hepcidin-25 (rho = -0,38; p = < 0, 01 and rho = -0,02; p = 0, 89, respectively) at baseline. Supplementation with VD significantly raised the serum concentration of serum 25(OH)D in the treatment group (from 54 (39-71) to 156 (120-190) nmol/L; p = < 0, 01)) but had no effect on any of the markers of hepcidin, erythropoiesis, or iron status in the entire cohort. However, we did observe an increase in hemoglobin (HB) levels and transferrin saturation (TSAT) as compared to the PBO group in a subgroup of patients with low baseline 25(OH)D levels (< 56 nmol/L). In contrast, in patients with high baseline 25(OH)D values (≥ 56 nmol/L), VD supplementation associated with a decrease in HB levels and TSAT (p = 0,056) within the VD group in addition to a decrease in hepcidin levels as compared to the PBO group. CONCLUSION High-dose VD supplementation had no discernible effect on markers of hepcidin or erythropoiesis in the entire study cohort. However, in patients with low baseline 25(OH)D levels, high-dose VD supplementation associated with beneficial effects on erythropoiesis and iron availability. In contrast, in patients with elevated baseline 25(OH)D levels, high-dose VD supplementation resulted in a decrease in hepcidin levels, most likely due to a deterioration in iron status.
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Affiliation(s)
| | - Per-Anton Westerberg
- grid.8993.b0000 0004 1936 9457Medical Sciences, Uppsala University, Uppsala, Sweden ,grid.460356.20000 0004 0449 0385Department of Medicine, Åland’s Central Hospital, 22100 Mariehamn, Finland
| | - Abdul Rashid Qureshi
- grid.4714.60000 0004 1937 0626Renal Medicine, CLINTEC, Karolinska Institutet, Stockholm, Sweden
| | - Soheir Beshara
- grid.4714.60000 0004 1937 0626Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Gunnar Sterner
- grid.411843.b0000 0004 0623 9987Renal Medicine, Skåne University Hospital, Malmö, Sweden
| | - Peter Bárány
- grid.4714.60000 0004 1937 0626Renal Medicine, CLINTEC, Karolinska Institutet, Stockholm, Sweden
| | - Torbjörn Linde
- grid.8993.b0000 0004 1936 9457Medical Sciences, Uppsala University, Uppsala, Sweden
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6
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Baringer S, Palsa K, Simpson IA, Connor JR. Apo- and holo- transferrin differentially interact with ferroportin and hephaestin to regulate iron release at the blood-brain barrier. RESEARCH SQUARE 2023:rs.3.rs-2429356. [PMID: 36711476 PMCID: PMC9882672 DOI: 10.21203/rs.3.rs-2429356/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Background : Apo- (iron free) and holo- (iron bound) transferrin (Tf) participate in precise regulation of brain iron uptake at endothelial cells of the blood-brain barrier. Apo-Tf indicates an iron deficient environment and stimulates iron release, while holo-Tf indicates an iron sufficient environment and suppresses additional iron release. Free iron is exported through ferroportin, with hephaestin as an aid to the process. Until now, the molecular mechanism of apo- and holo-Tf's influence on iron release was largely unknown. Methods : Here we use a variety of cell culture techniques, including co-immunoprecipitation and proximity ligation assay, in iPSC-derived endothelial cells and HEK 293 cells to investigate the mechanism of apo- and holo-Tf's influence over iron release. We placed our findings in physiological context by further deciphering how hepcidin played a role in this mechanism as well. Results : We demonstrate that holo-Tf induces the internalization of ferroportin through the established ferroportin degradation pathway. Furthermore, holo-Tf directly binds to ferroportin, whereas apo-Tf directly binds to hephaestin. Only pathological levels of hepcidin disrupt the interaction between holo-Tf and ferroportin, and no amount of hepcidin disrupts the interaction between apo-Tf and hephaestin. The disruption of the holo-Tf and ferroportin interaction by hepcidin is due to hepcidin's ability to rapidly internalize ferroportin compared to holo-Tf. Conclusions : These novel findings provide a molecular mechanism for apo- and holo-Tf regulation of iron release from endothelial cells. They further demonstrate how hepcidin impacts these protein-protein interactions, and offer a model for how holo-Tf and hepcidin corporate to suppress iron release. We have established a more thorough understanding of the mechanisms behind iron release regulation with great clinical impact for a variety of neurological conditions in which iron release is dysregulated.
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7
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Baringer SL, Palsa K, Simpson IA, Connor JR. Apo- and holo- transferrin differentially interact with ferroportin and hephaestin to regulate iron release at the blood-brain barrier. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.10.522344. [PMID: 36712094 PMCID: PMC9882075 DOI: 10.1101/2023.01.10.522344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Background Apo- (iron free) and holo- (iron bound) transferrin (Tf) participate in precise regulation of brain iron uptake at endothelial cells of the blood-brain barrier. Apo-Tf indicates an iron deficient environment and stimulates iron release, while holo-Tf indicates an iron sufficient environment and suppresses additional iron release. Free iron is exported through ferroportin, with hephaestin as an aid to the process. Until now, the molecular mechanism of apo- and holo-Tf's influence on iron release was largely unknown. Methods Here we use a variety of cell culture techniques, including co-immunoprecipitation and proximity ligation assay, in iPSC-derived endothelial cells and HEK 293 cells to investigate the mechanism of apo- and holo-Tf's influence over iron release. We placed our findings in physiological context by further deciphering how hepcidin played a role in this mechanism as well. Results We demonstrate that holo-Tf induces the internalization of ferroportin through the established ferroportin degradation pathway. Furthermore, holo-Tf directly binds to ferroportin, whereas apo-Tf directly binds to hephaestin. Only pathological levels of hepcidin disrupt the interaction between holo-Tf and ferroportin, and no amount of hepcidin disrupts the interaction between apo-Tf and hephaestin. The disruption of the holo-Tf and ferroportin interaction by hepcidin is due to hepcidin's ability to rapidly internalize ferroportin compared to holo-Tf. Conclusions These novel findings provide a molecular mechanism for apo- and holo-Tf regulation of iron release from endothelial cells. They further demonstrate how hepcidin impacts these protein-protein interactions, and offer a model for how holo-Tf and hepcidin corporate to suppress iron release. We have established a more thorough understanding of the mechanisms behind iron release regulation with great clinical impact for a variety of neurological conditions in which iron release is dysregulated.
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Affiliation(s)
| | - Kondaiah Palsa
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
| | - Ian A. Simpson
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA, USA
| | - James R. Connor
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
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Pal A, Cerchiaro G, Rani I, Ventriglia M, Rongioletti M, Longobardi A, Squitti R. Iron in Alzheimer's Disease: From Physiology to Disease Disabilities. Biomolecules 2022; 12:1248. [PMID: 36139084 PMCID: PMC9496246 DOI: 10.3390/biom12091248] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 08/29/2022] [Accepted: 09/02/2022] [Indexed: 11/19/2022] Open
Abstract
Reactive oxygen species (ROS) play a key role in the neurodegeneration processes. Increased oxidative stress damages lipids, proteins, and nucleic acids in brain tissue, and it is tied to the loss of biometal homeostasis. For this reason, attention has been focused on transition metals involved in several biochemical reactions producing ROS. Even though a bulk of evidence has uncovered the role of metals in the generation of the toxic pathways at the base of Alzheimer's disease (AD), this matter has been sidelined by the advent of the Amyloid Cascade Hypothesis. However, the link between metals and AD has been investigated in the last two decades, focusing on their local accumulation in brain areas known to be critical for AD. Recent evidence revealed a relation between iron and AD, particularly in relation to its capacity to increase the risk of the disease through ferroptosis. In this review, we briefly summarize the major points characterizing the function of iron in our body and highlight why, even though it is essential for our life, we have to monitor its dysfunction, particularly if we want to control our risk of AD.
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Affiliation(s)
- Amit Pal
- Department of Biochemistry, All India Institute of Medical Sciences (AIIMS), Kalyani 741245, West Bengal, India
| | - Giselle Cerchiaro
- Center for Natural Sciences and Humanities, Federal University of ABC (UFABC), Avenida dos Estados, 5001, Bl.B, Santo André 09210-580, SP, Brazil
| | - Isha Rani
- Department of Biochemistry, Maharishi Markandeshwar University (MMU), Mullana, Ambala 133203, Haryana, India
| | - Mariacarla Ventriglia
- Fatebenefratelli Foundation for Health Research and Education, AFaR Division, 00186 Rome, Italy
| | - Mauro Rongioletti
- Department of Laboratory Medicine, Research and Development Division, Fatebenefratelli Isola Tiberina, Gemelli Isola, 00186 Rome, Italy
| | - Antonio Longobardi
- Molecular Markers Laboratory, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, 25125 Brescia, Italy
| | - Rosanna Squitti
- Department of Laboratory Medicine, Research and Development Division, Fatebenefratelli Isola Tiberina, Gemelli Isola, 00186 Rome, Italy
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Koury MJ, Agarwal R, Chertow GM, Eckardt K, Fishbane S, Ganz T, Haase VH, Hanudel MR, Parfrey PS, Pergola PE, Roy‐Chaudhury P, Tumlin JA, Anders R, Farag YMK, Luo W, Minga T, Solinsky C, Vargo DL, Winkelmayer WC. Erythropoietic effects of vadadustat in patients with anemia associated with chronic kidney disease. Am J Hematol 2022; 97:1178-1188. [PMID: 35751858 PMCID: PMC9543410 DOI: 10.1002/ajh.26644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 06/20/2022] [Indexed: 11/09/2022]
Abstract
Patients with chronic kidney disease (CKD) develop anemia largely because of inappropriately low erythropoietin (EPO) production and insufficient iron available to erythroid precursors. In four phase 3, randomized, open-label, clinical trials in dialysis-dependent and non-dialysis-dependent patients with CKD and anemia, the hypoxia-inducible factor prolyl hydroxylase inhibitor, vadadustat, was noninferior to the erythropoiesis-stimulating agent, darbepoetin alfa, in increasing and maintaining target hemoglobin concentrations. In these trials, vadadustat increased the concentrations of serum EPO, the numbers of circulating erythrocytes, and the numbers of circulating reticulocytes. Achieved hemoglobin concentrations were similar in patients treated with either vadadustat or darbepoetin alfa, but compared with patients receiving darbepoetin alfa, those receiving vadadustat had erythrocytes with increased mean corpuscular volume and mean corpuscular hemoglobin, while the red cell distribution width was decreased. Increased serum transferrin concentrations, as measured by total iron-binding capacity, combined with stable serum iron concentrations, resulted in decreased transferrin saturation in patients randomized to vadadustat compared with patients randomized to darbepoetin alfa. The decreases in transferrin saturation were associated with relatively greater declines in serum hepcidin and ferritin in patients receiving vadadustat compared with those receiving darbepoetin alfa. These results for serum transferrin saturation, hepcidin, ferritin, and erythrocyte indices were consistent with improved iron availability in the patients receiving vadadustat. Thus, overall, vadadustat had beneficial effects on three aspects of erythropoiesis in patients with anemia associated with CKD: increased endogenous EPO production, improved iron availability to erythroid cells, and increased reticulocytes in the circulation.
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Affiliation(s)
- Mark J. Koury
- Division of Hematology/Oncology, Department of MedicineVanderbilt University Medical CenterNashvilleTennesseeUSA
| | - Rajiv Agarwal
- Department of Medicine, Division of NephrologyIndiana University School of MedicineIndianapolisIndianaUSA
| | | | - Kai‐Uwe Eckardt
- Department of Nephrology and Medical Intensive CareCharité – Universitätsmedizin BerlinBerlinGermany
| | - Steven Fishbane
- Division of Nephrology, Department of MedicineHofstra Northwell School of MedicineGreat NeckNew YorkUSA
| | - Tomas Ganz
- Department of Medicine and Pathology, David Geffen School of MedicineUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - Volker H. Haase
- Department of MedicineVanderbilt University Medical CenterNashvilleTennesseeUSA
- Department of Medical Cell BiologyUppsala UniversityUppsalaSweden
| | - Mark R. Hanudel
- Department of Pediatrics, Division of Pediatric Nephrology, David Geffen School of MedicineUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - Patrick S. Parfrey
- Department of MedicineMemorial UniversitySt John'sNewfoundland and LabradorCanada
| | | | | | | | | | | | - Wenli Luo
- Akebia Therapeutics, Inc.CambridgeMassachusettsUSA
| | - Todd Minga
- Akebia Therapeutics, Inc.CambridgeMassachusettsUSA
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10
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A small molecule redistributes iron in ferroportin-deficient mice and patient-derived primary macrophages. Proc Natl Acad Sci U S A 2022; 119:e2121400119. [PMID: 35737834 PMCID: PMC9245668 DOI: 10.1073/pnas.2121400119] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Iron misdistribution underlies various diseases, ranging from anemia to neurodegeneration, but approaches to addressing this general problem are lacking. We recently reported that a small molecule natural product, hinokitiol, is capable of restoring hemoglobinization in various animal models with missing iron transporters. We now show that hinokitiol is capable of redistributing iron systemically, which in turn restores iron homeostasis in ferroportin-deficient mice and in primary macrophages derived from patients with ferroportin disease. We also elucidated the stepwise mechanism of hinokitiol-mediated iron redistribution and physiological restoration. Together, these results provide foundational support for using a molecular prosthetics approach for better understanding and possibly treating iron misdistribution. Deficiencies of the transmembrane iron-transporting protein ferroportin (FPN1) cause the iron misdistribution that underlies ferroportin disease, anemia of inflammation, and several other human diseases and conditions. A small molecule natural product, hinokitiol, was recently shown to serve as a surrogate transmembrane iron transporter that can restore hemoglobinization in zebrafish deficient in other iron transporting proteins and can increase gut iron absorption in FPN1-deficient flatiron mice. However, whether hinokitiol can restore normal iron physiology in FPN1-deficient animals or primary cells from patients and the mechanisms underlying such targeted activities remain unknown. Here, we show that hinokitiol redistributes iron from the liver to red blood cells in flatiron mice, thereby increasing hemoglobin and hematocrit. Mechanistic studies confirm that hinokitiol functions as a surrogate transmembrane iron transporter to release iron trapped within liver macrophages, that hinokitiol-Fe complexes transfer iron to transferrin, and that the resulting transferrin-Fe complexes drive red blood cell maturation in a transferrin-receptor–dependent manner. We also show in FPN1-deficient primary macrophages derived from patients with ferroportin disease that hinokitiol moves labile iron from inside to outside cells and decreases intracellular ferritin levels. The mobilization of nonlabile iron is accompanied by reductions in intracellular ferritin, consistent with the activation of regulated ferritin proteolysis. These findings collectively provide foundational support for the translation of small molecule iron transporters into therapies for human diseases caused by iron misdistribution.
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11
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Genome-wide meta-analysis of iron status biomarkers and the effect of iron on all-cause mortality in HUNT. Commun Biol 2022; 5:591. [PMID: 35710628 PMCID: PMC9203493 DOI: 10.1038/s42003-022-03529-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 05/24/2022] [Indexed: 01/19/2023] Open
Abstract
Iron is essential for many biological processes, but iron levels must be tightly regulated to avoid harmful effects of both iron deficiency and overload. Here, we perform genome-wide association studies on four iron-related biomarkers (serum iron, serum ferritin, transferrin saturation, total iron-binding capacity) in the Trøndelag Health Study (HUNT), the Michigan Genomics Initiative (MGI), and the SardiNIA study, followed by their meta-analysis with publicly available summary statistics, analyzing up to 257,953 individuals. We identify 123 genetic loci associated with iron traits. Among 19 novel protein-altering variants, we observe a rare missense variant (rs367731784) in HUNT, which suggests a role for DNAJC13 in transferrin recycling. We further validate recently published results using genetic risk scores for each biomarker in HUNT (6% variance in serum iron explained) and present linear and non-linear Mendelian randomization analyses of the traits on all-cause mortality. We find evidence of a harmful effect of increased serum iron and transferrin saturation in linear analyses that estimate population-averaged effects. However, there was weak evidence of a protective effect of increasing serum iron at the very low end of its distribution. Our findings contribute to our understanding of the genes affecting iron status and its consequences on human health. A GWAS on the four major iron-related biomarkers is conducted using data from the Trøndelag Health Study (HUNT), Michigan Genomics Initiative (MGI), and SardiNIA study, to identify 123 loci associated with iron homeostasis and effect on all-cause mortality.
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12
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Li Y, Miller I, Prasad P, George NA, Parrow NL, Fleming RE. Effects of Exogenous Transferrin on the Regulation of Iron Metabolism and Erythropoiesis in Iron Deficiency With or Without Anemia. Front Physiol 2022; 13:893149. [PMID: 35634155 PMCID: PMC9132588 DOI: 10.3389/fphys.2022.893149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Erythropoietic response is controlled not only by erythropoietin but also by iron. In addition to its role in iron delivery, transferrin also functions as a signaling molecule, with effects on both iron homeostasis and erythropoiesis. We investigated hematologic parameters, iron status and expression of key proteins, including the hepatic iron regulatory protein hepcidin and the suppressive erythroid factor Erfe, in mice subject to dietary iron deficiency with and without anemia. The acute effect of iron on these parameters was investigated by administration of exogenous iron-loaded transferrin (holoTf) in each of the mouse models. Serum iron in mice with iron deficiency (ID) is modestly lower with hematologic parameters maintained by utilization of iron stores in mice with ID. As expected, erythropoietin expression and concentration, along with marrow Erfe are unaffected in ID mice. Administration of holoTf restores serum iron and Tf saturation levels to those observed in control mice and results in an increase in hepcidin compared to ID mice not treated with holoTf. The expression of the Bmp signaling molecule Bmp6 is not significantly increased following Tf treatment in ID mice. Thus, the expression level of the gene encoding hepcidin, Hamp1, is increased relative to Bmp6 expression in ID mice following treatment with holoTf, leading us to speculate that Tf saturation may influence Bmp sensitivity. In mice with iron deficiency anemia (IDA), decreased hematologic parameters were accompanied by pronounced decreases in serum and tissue iron concentrations, and an increase in serum erythropoietin. In the absence of exogenous holoTf, the greater serum erythropoietin was not reflected by an increase in marrow Erfe expression. HoloTf administration did not acutely change serum Epo in IDA mice. Marrow Erfe expression was, however, markedly increased in IDA mice following holoTf, plausibly accounting for the lack of an increase in Hamp1 following holoTf treatment in the IDA mice. The increase in Erfe despite no change in erythropoietin suggests that Tf acts to increase erythropoietin sensitivity. These observations underscore the importance of Tf in modulating the erythropoietic response in recovery from iron deficiency anemia, with implications for other stress erythropoiesis conditions.
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Affiliation(s)
- Yihang Li
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO, United States
| | - Ian Miller
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO, United States
| | - Princy Prasad
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO, United States
| | - Nisha Ajit George
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO, United States
| | - Nermi L. Parrow
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO, United States
| | - Robert E. Fleming
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO, United States
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, United States
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13
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Kaynar LA, Gökçen S, Can F, Yeğin ZA, Özkurt ZN, Yağcı M. Comparison of daily oral iron replacement therapy with every other day treatment in female reproductive age patients with iron-deficiency anemia. Ann Hematol 2022; 101:1459-1464. [PMID: 35460388 DOI: 10.1007/s00277-022-04835-6] [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: 11/16/2021] [Accepted: 04/03/2022] [Indexed: 11/29/2022]
Abstract
Iron-deficiency anemia (IDA) is accepted as the most common cause of anemia in the world. The main goals of iron replacement therapy are to normalize the hemoglobin level and to replace iron stores. Current guidelines for treating iron deficiency recommend daily divided doses of iron to increase absorption. Hepcidin is a key regulator of systemic iron balance and acts in harmony with intracellular iron metabolism. Daily dosing and divided doses may increase serum hepcidin and decrease iron absorption. In this study, it was aimed to compare the effectiveness of daily and every other day oral iron replacement therapy in women of reproductive age with iron-deficiency anemia. We included premenopausal female patients aged between 18 and 50 years with iron-deficiency anemia. Forty patients were given oral iron therapy at a daily dose of 2*80 mg (iron sulfate). Forty-three patients were given iron treatment at a dose of 2*80 mg (iron sulfate) every other day. After 2 months of oral iron therapy, there was a significant improvement in hemoglobin, mean corpuscular volume, serum iron, total iron-binding capacity, and transferrin saturation in both groups. The values of hemoglobin, serum iron, transferrin saturation, and ferritin significantly increased at the end of the treatment for both groups. Although the median hepcidin level on the 15th-day measurement in the every other day treatment group was higher than that in the daily treatment group, there was no significant difference. As a result, the patients' compliance with the treatment can be increased by offering treatment every other day instead of daily, since it provides similar treatment effectiveness.
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Affiliation(s)
- Lale Aydın Kaynar
- Department of Adult Hematology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey.
| | - Sanem Gökçen
- Department of Adult Hematology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey
| | - Ferda Can
- Department of Adult Hematology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey
| | - Zeynep Arzu Yeğin
- Department of Adult Hematology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey
| | - Zübeyde Nur Özkurt
- Department of Adult Hematology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey
| | - Münci Yağcı
- Department of Adult Hematology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey
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14
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Hanudel MR, Czaya B, Wong S, Jung G, Chua K, Qiao B, Gabayan V, Ganz T. Renoprotective effects of ferric citrate in a mouse model of chronic kidney disease. Sci Rep 2022; 12:6695. [PMID: 35461329 PMCID: PMC9035171 DOI: 10.1038/s41598-022-10842-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 04/06/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractIn chronic kidney disease, ferric citrate has been shown to be an effective phosphate binder and source of enteral iron; however, the effects of ferric citrate on the kidney have been less well-studied. Here, in Col4α3 knockout mice—a murine model of progressive chronic kidney disease, we evaluated the effects of five weeks of 1% ferric citrate dietary supplementation. As expected, ferric citrate lowered serum phosphate concentrations and increased serum iron levels in the Col4α3 knockout mice. Consistent with decreased enteral phosphate absorption and possibly improved iron status, ferric citrate greatly reduced circulating fibroblast growth factor 23 levels. Interestingly, ferric citrate also lessened systemic inflammation, improved kidney function, reduced albuminuria, and decreased kidney inflammation and fibrosis, suggesting renoprotective effects of ferric citrate in the setting of chronic kidney disease. The factors mediating possible ferric citrate renoprotection, the mechanisms by which they may act, and whether ferric citrate affects chronic kidney disease progression in humans deserves further study.
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15
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Fisher AL, Babitt JL. Coordination of iron homeostasis by bone morphogenetic proteins: Current understanding and unanswered questions. Dev Dyn 2022; 251:26-46. [PMID: 33993583 PMCID: PMC8594283 DOI: 10.1002/dvdy.372] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/15/2021] [Accepted: 05/07/2021] [Indexed: 01/19/2023] Open
Abstract
Iron homeostasis is tightly regulated to balance the iron requirement for erythropoiesis and other vital cellular functions, while preventing cellular injury from iron excess. The liver hormone hepcidin is the master regulator of systemic iron balance by controlling the degradation and function of the sole known mammalian iron exporter ferroportin. Liver hepcidin expression is coordinately regulated by several signals that indicate the need for more or less iron, including plasma and tissue iron levels, inflammation, and erythropoietic drive. Most of these signals regulate hepcidin expression by modulating the activity of the bone morphogenetic protein (BMP)-SMAD pathway, which controls hepcidin transcription. Genetic disorders of iron overload and iron deficiency have identified several hepatocyte membrane proteins that play a critical role in mediating the BMP-SMAD and hepcidin regulatory response to iron. However, the precise molecular mechanisms by which serum and tissue iron levels are sensed to regulate BMP ligand production and promote the physical and/or functional interaction of these proteins to modulate SMAD signaling and hepcidin expression remain uncertain. This critical commentary will focus on the current understanding and key unanswered questions regarding how the liver senses iron levels to regulate BMP-SMAD signaling and thereby hepcidin expression to control systemic iron homeostasis.
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Affiliation(s)
| | - Jodie L Babitt
- Corresponding author: Jodie L Babitt, Division of Nephrology, Program in Membrane Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA. Mailing address: 185 Cambridge St., CPZN-8208, Boston, MA 02114. Telephone: +1 (617) 643-3181.
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16
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Zhang R, Huang X, Li Y, Yu Z, Wu Y, Zha B, Ding H, Zang S, Liu J. Serum ferritin as a risk factor for type 2 diabetes mellitus, regulated by liver transferrin receptor 2. Endocr Connect 2021; 10:1513-1521. [PMID: 34727090 PMCID: PMC8679876 DOI: 10.1530/ec-21-0316] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 11/02/2021] [Indexed: 11/08/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate the effect of TFR2 on iron storage in type 2 diabetes. METHODS A cross-sectional study was conducted among 1938 participants from the Jiangchuan Community of Shanghai. A total of 784 participants with T2DM and 1154 normal participants (non-T2DM) were enrolled in this study. Serum ferritin, fasting blood glucose, postprandial blood glucose, and HbA1C (glycated hemoglobin A1c) levels were determined. Eighteen Wistar male rats were randomly assigned into three groups (n = 6/group): rats in a high-fat diet streptozotocin (HFD+STZ) group were fed with HFD for 4 weeks and intraperitoneally injected with streptozotocin (STZ); rats in a control group were fed with a standard diet for 4 weeks and intraperitoneally injected with buffer; rats in an STZ group were fed with a standard diet for 4 weeks and intraperitoneally injected with streptozotocin. Glucose tolerance test was performed at the end of the study. Blood samples and liver tissues were assessed for liver TFR2, blood glucose, serum ferritin, and iron levels. RESULTS The mean serum ferritin level of T2DM participants was significantly higher than that of the control group (227 (140-352) vs 203.5 (130.5-312) ng/mL, P < 0.05). Serum ferritin level was an independent risk factor for T2DM (high ferritin group vs low ferritin group, 1.304 (1.03-1.651), P < 0.05). Diabetic rats showed reduced liver TFR2 levels, with increased serum ferritin levels. CONCLUSION T2DM participants exhibited iron disorder with elevated serum ferritin levels. Elevated serum ferritin levels in diabetic rats were accompanied by reduced liver TFR2 levels.
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Affiliation(s)
- Rui Zhang
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
| | - Xinmei Huang
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
| | - Yue Li
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
| | - Zhiyan Yu
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
| | - Yueyue Wu
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
| | - Bingbing Zha
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
| | - Heyuan Ding
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
| | - Shufei Zang
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
- Correspondence should be addressed to S Zang or J Liu: or
| | - Jun Liu
- Department of Endocrinology, Shanghai Fifth People’s Hospital affiliated to Fudan University, Minhang District, Shanghai, People’s Republic of China
- Correspondence should be addressed to S Zang or J Liu: or
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17
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Kim HY, Lee JM, Lee YS, Li S, Lee SJ, Bae SC, Jung HS. Runx3 regulates iron metabolism via modulation of BMP signalling. Cell Prolif 2021; 54:e13138. [PMID: 34611951 PMCID: PMC8666273 DOI: 10.1111/cpr.13138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 09/13/2021] [Accepted: 09/20/2021] [Indexed: 12/11/2022] Open
Abstract
Objectives Runx3, a member of the Runx family of transcription factors, has been studied as a tumour suppressor and key player of organ development. In a previous study, we reported differentiation failure and excessive angiogenesis in the liver of Runx3 knock‐out (KO) mice. Here, we examined a function of the Runx3 in liver, especially in iron metabolism. Methods We performed histological and immunohistological analyses of the Runx3 KO mouse liver. RNA‐sequencing analyses were performed on primary hepatocytes isolated from Runx3 conditional KO (cKO) mice. The effect of Runx3 knock‐down (KD) was also investigated using siRNA‐mediated KD in functional human hepatocytes and human hepatocellular carcinoma cells. Result We observed an iron‐overloaded liver with decreased expression of hepcidin in Runx3 KO mice. Expression of BMP6, a regulator of hepcidin transcription, and activity of the BMP pathway were decreased in the liver tissue of Runx3 KO mice. Transcriptome analysis on primary hepatocytes isolated from Runx3 cKO mice also revealed that iron‐induced increase in BMP6 was mediated by Runx3. Similar results were observed in Runx3 knock‐down experiments using HepaRG cells and HepG2 cells. Finally, we showed that Runx3 enhanced the activity of the BMP6 promoter by responding to iron stimuli in the hepatocytes. Conclusion In conclusion, we suggest that Runx3 plays important roles in iron metabolism of the liver through regulation of BMP signalling.
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Affiliation(s)
- Hyun-Yi Kim
- Division in Anatomy and Developmental Biology, Department of Oral Biology, Oral Science Research Center, BK21 FOUR, Yonsei University College of Dentistry, Seoul, Korea
| | - Jong-Min Lee
- Division in Anatomy and Developmental Biology, Department of Oral Biology, Oral Science Research Center, BK21 FOUR, Yonsei University College of Dentistry, Seoul, Korea
| | - You-Soub Lee
- Department of Biochemistry, School of Medicine, and Institute for Tumor Research, Chungbuk National University, Cheongju, Korea
| | - Shujin Li
- Division in Anatomy and Developmental Biology, Department of Oral Biology, Oral Science Research Center, BK21 FOUR, Yonsei University College of Dentistry, Seoul, Korea
| | - Seung-Jun Lee
- Division in Anatomy and Developmental Biology, Department of Oral Biology, Oral Science Research Center, BK21 FOUR, Yonsei University College of Dentistry, Seoul, Korea
| | - Suk-Chul Bae
- Department of Biochemistry, School of Medicine, and Institute for Tumor Research, Chungbuk National University, Cheongju, Korea
| | - Han-Sung Jung
- Division in Anatomy and Developmental Biology, Department of Oral Biology, Oral Science Research Center, BK21 FOUR, Yonsei University College of Dentistry, Seoul, Korea
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18
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Mazgaj R, Lipiński P, Szudzik M, Jończy A, Kopeć Z, Stankiewicz AM, Kamyczek M, Swinkels D, Żelazowska B, Starzyński RR. Comparative Evaluation of Sucrosomial Iron and Iron Oxide Nanoparticles as Oral Supplements in Iron Deficiency Anemia in Piglets. Int J Mol Sci 2021; 22:9930. [PMID: 34576090 PMCID: PMC8466487 DOI: 10.3390/ijms22189930] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/06/2021] [Accepted: 09/11/2021] [Indexed: 12/15/2022] Open
Abstract
Iron deficiency is the most common mammalian nutritional disorder. However, among mammalian species iron deficiency anemia (IDA), occurs regularly only in pigs. To cure IDA, piglets are routinely injected with high amounts of iron dextran (FeDex), which can lead to perturbations in iron homeostasis. Here, we evaluate the therapeutic efficacy of non-invasive supplementation with Sucrosomial iron (SI), a highly bioavailable iron supplement preventing IDA in humans and mice and various iron oxide nanoparticles (IONPs). Analysis of red blood cell indices and plasma iron parameters shows that not all iron preparations used in the study efficiently counteracted IDA comparable to FeDex-based supplementation. We found no signs of iron toxicity of any tested iron compounds, as evaluated based on the measurement of several toxicological markers that could indicate the occurrence of oxidative stress or inflammation. Neither SI nor IONPs increased hepcidin expression with alterations in ferroportin (FPN) protein level. Finally, the analysis of the piglet gut microbiota indicates the individual pattern of bacterial diversity across taxonomic levels, independent of the type of supplementation. In light of our results, SI but not IONPs used in the experiment emerges as a promising nutritional iron supplement, with a high potential to correct IDA in piglets.
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Affiliation(s)
- Rafał Mazgaj
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology PAS, 28-130 Jastrzębiec, Poland; (R.M.); (M.S.); (A.J.); (Z.K.); (A.M.S.); (B.Ż.)
| | - Paweł Lipiński
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology PAS, 28-130 Jastrzębiec, Poland; (R.M.); (M.S.); (A.J.); (Z.K.); (A.M.S.); (B.Ż.)
| | - Mateusz Szudzik
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology PAS, 28-130 Jastrzębiec, Poland; (R.M.); (M.S.); (A.J.); (Z.K.); (A.M.S.); (B.Ż.)
| | - Aneta Jończy
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology PAS, 28-130 Jastrzębiec, Poland; (R.M.); (M.S.); (A.J.); (Z.K.); (A.M.S.); (B.Ż.)
| | - Zuzanna Kopeć
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology PAS, 28-130 Jastrzębiec, Poland; (R.M.); (M.S.); (A.J.); (Z.K.); (A.M.S.); (B.Ż.)
| | - Adrian M. Stankiewicz
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology PAS, 28-130 Jastrzębiec, Poland; (R.M.); (M.S.); (A.J.); (Z.K.); (A.M.S.); (B.Ż.)
| | - Marian Kamyczek
- Pig Hybridization Centre, National Research Institute of Animal Production, 43-246 Pawłowice, Poland;
| | - Dorine Swinkels
- Department of Laboratory Medicine (TLM 830), Radboud University Nijmegen Medical Center, 6525 GA Nijmegen, The Netherlands;
- Hepcidin Analysis, Department of Laboratory Medicine, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Beata Żelazowska
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology PAS, 28-130 Jastrzębiec, Poland; (R.M.); (M.S.); (A.J.); (Z.K.); (A.M.S.); (B.Ż.)
| | - Rafał R. Starzyński
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology PAS, 28-130 Jastrzębiec, Poland; (R.M.); (M.S.); (A.J.); (Z.K.); (A.M.S.); (B.Ż.)
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Petrillo S, Manco M, Altruda F, Fagoonee S, Tolosano E. Liver Sinusoidal Endothelial Cells at the Crossroad of Iron Overload and Liver Fibrosis. Antioxid Redox Signal 2021; 35:474-486. [PMID: 32689808 DOI: 10.1089/ars.2020.8168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Significance: Liver fibrosis results from different etiologies and represents one of the most serious health issues worldwide. Fibrosis is the outcome of chronic insults on the liver and is associated with several factors, including abnormal iron metabolism. Recent Advances: Multiple mechanisms underlying the profibrogenic role of iron have been proposed. The pivotal role of liver sinusoidal endothelial cells (LSECs) in iron-level regulation, as well as their morphological and molecular dedifferentiation occurring in liver fibrosis, has encouraged research on LSECs as prime regulators of very early fibrotic events. Importantly, normal differentiated LSECs may act as gatekeepers of fibrogenesis by maintaining the quiescence of hepatic stellate cells, while LSECs capillarization precedes the onset of liver fibrosis. Critical Issues: In the present review, the morphological and molecular alterations occurring in LSECs after liver injury are addressed in an attempt to highlight how vascular dysfunction promotes fibrogenesis. In particular, we discuss in depth how a vicious loop can be established in which iron dysregulation and LSEC dedifferentiation synergize to exacerbate and promote the progression of liver fibrosis. Future Directions: LSECs, due to their pivotal role in early liver fibrosis and iron homeostasis, show great promises as a therapeutic target. In particular, new strategies can be devised for restoring LSECs differentiation and thus their role as regulators of iron homeostasis, hence preventing the progression of liver fibrosis or, even better, promoting its regression. Antioxid. Redox Signal. 35, 474-486.
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Affiliation(s)
- Sara Petrillo
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Marta Manco
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Fiorella Altruda
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Sharmila Fagoonee
- Institute of Biostructure and Bioimaging, CNR c/o Molecular Biotechnology Center, Torino, Italy
| | - Emanuela Tolosano
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Torino, Italy
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20
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Innovative oral sucrosomial ferric pyrophosphate-based supplementation rescues suckling piglets from iron deficiency anemia similarly to commonly used parenteral therapy with iron dextran. ANNALS OF ANIMAL SCIENCE 2021. [DOI: 10.2478/aoas-2020-0084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Iron deficiency is the most common mammalian nutritional deficiency during the neonatal period. However, among mammalian species neonatal iron deficiency anemia (IDA), the most severe consequence of iron scarcity, occurs regularly in pigs. Although intramuscular supplementation of piglets with high amounts of iron dextran (FeDex) is largely considered an appropriate preventive therapy for IDA prophylaxis, an increasing evidence shows that it negatively affects pig physiology. The aim of our study was to evaluate the efficacy of non-invasive supplementation of piglets with sucrosomial ferric pyrophosphate (SFP), a highly bioavailable dietary iron supplement in preventing IDA, in humans and mice. Results of our study show that SFP given to piglets per os in the amount of 6 mg Fe daily efficiently counteracts IDA at a rate comparable with the traditional FeDex-based supplementation (100 mgFe/kG b.w.; i.m. injection). This was indicated by physiological values of red blood cell indices and plasma iron parameters measured in 28-day old piglets. Moreover, SFP-supplemented piglets showed significantly lower (P ≤0.05) plasma level of 8-isoprostane, a biomarker for oxidative stress compared to FeDex-treated animals, implying lesser toxicity of this order of iron replenishment. Finally, supplementation with SFP does not increase considerably the blood plasma hepcidin, a peptide that acts to inhibit iron absorption from the diet. SFP emerges as a promising nutritional iron supplement, with a high potential to be adopted in the postnatal period.
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21
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Effect of hepcidin antagonists on anemia during inflammatory disorders. Pharmacol Ther 2021; 226:107877. [PMID: 33895185 DOI: 10.1016/j.pharmthera.2021.107877] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 04/20/2021] [Indexed: 12/11/2022]
Abstract
Iron is an essential element for the mammalian body however, its homeostasis must be regulated accurately for appropriate physiological functioning. Alterations in physiological iron levels can lead to moderate to severe iron disorders like chronic and acute iron deficiency (anemia) or iron overload. Hepcidin plays an important role in regulating homeostasis between circulating iron and stored iron in the cells as well as the absorption of dietary iron in the intestine. Inflammatory disorders restrict iron absorption from food due to increased circulating levels of hepcidin. Increased production of hepcidin causes ubiquitination of ferroportin (FPN) leading to its degradation, thereby retaining iron in the spleen, duodenal enterocytes, macrophages, and hepatocytes. Hepcidin inhibitors and antagonists play a consequential role to ameliorate inflammation-associated anemia. Many natural and synthesized compounds, able to reduce hepcidin expression during inflammation have been identified in recent years. Few of which are currently at various phases of clinical trial. This article comprises a comprehensive review of therapeutic approaches for the efficient treatment of anemia associated with inflammation. Many strategies have been developed targeting the hepcidin-FPN axis to rectify iron disorders. Hepcidin modulation with siRNAs, antibodies, chemical compounds, and plant extracts provides new insights for developing advanced therapeutics for iron-related disorders. Hepcidin antagonist's treatment has a high potential to improve iron status in patients with iron disorders, but their clinical success needs further recognition along with the identification and application of new therapeutic approaches.
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22
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Hanudel MR, Wong S, Jung G, Qiao B, Gabayan V, Zuk A, Ganz T. Amelioration of chronic kidney disease-associated anemia by vadadustat in mice is not dependent on erythroferrone. Kidney Int 2021; 100:79-89. [PMID: 33811979 DOI: 10.1016/j.kint.2021.03.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 02/02/2021] [Accepted: 03/10/2021] [Indexed: 02/06/2023]
Abstract
Vadadustat is an investigational hypoxia-inducible factor prolyl hydroxylase inhibitor that increases endogenous erythropoietin production and has been shown to decrease hepcidin levels, ameliorate iron restriction, and increase hemoglobin concentrations in anemic patients with chronic kidney disease (CKD). In studies of physiological responses to other erythropoietic stimuli, erythropoietin induced erythroblast secretion of erythroferrone (ERFE), which acts on the liver to suppress hepcidin production and mobilize iron for erythropoiesis. We therefore investigated whether vadadustat effects on erythropoiesis and iron metabolism are dependent on ERFE. Wild type and ERFE knockout mice with and without CKD were treated with vadadustat or vehicle. In both wild type and ERFE knockout CKD models, vadadustat was similarly effective, as evidenced by normalized hemoglobin concentrations, increased expression of duodenal iron transporters, lower serum hepcidin levels, and decreased tissue iron concentrations. This is consistent with ERFE-independent increased iron mobilization. Vadadustat treatment also lowered serum urea nitrogen and creatinine concentrations and decreased expression of kidney fibrosis markers. Lastly, vadadustat affected fibroblast growth factor 23 (FGF23) profiles: in non-CKD mice, vadadustat increased plasma total FGF23 out of proportion to intact FGF23, consistent with the known effects of hypoxia-inducible factor-1α and erythropoietin on FGF23 production and metabolism. However, in the mice with CKD, vadadustat markedly decreased both total and intact FGF23, effects likely contributed to by the reduced loss of kidney function. Thus, in this CKD model, vadadustat ameliorated anemia independently of ERFE, improved kidney parameters, and decreased FGF23. How vadadustat affects CKD progression in humans warrants future studies.
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Affiliation(s)
- Mark R Hanudel
- Department of Pediatrics, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, USA.
| | - Shirley Wong
- Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, USA
| | - Grace Jung
- Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, USA
| | - Bo Qiao
- Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, USA
| | - Victoria Gabayan
- Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, USA
| | - Anna Zuk
- Research and Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts, USA
| | - Tomas Ganz
- Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, USA
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Powers JM, Auerbach M. Iron supplementation in infants: a reflection on hepcidin and fractional iron absorption. Am J Clin Nutr 2020; 112:909-910. [PMID: 32844200 DOI: 10.1093/ajcn/nqaa224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Affiliation(s)
- Jacquelyn M Powers
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.,Texas Children's Cancer and Hematology Centers, Houston, TX, USA
| | - Michael Auerbach
- School of Medicine, Georgetown University, Washington, DC, USA.,Private Practice, Baltimore, MD, USA
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Abstract
Primary hepatocytes are a vital tool in various biomedical research disciplines, serving as an ex vivo model for liver physiology. Obtaining high yields of viable primary mouse hepatocytes is technically challenging, limiting their use. Here, we present an improved protocol based on the classic two-step collagenase perfusion technique. The liver is washed by perfusion, hepatocytes are dissociated by collagenase, separated from other cells, and cultured. This protocol was optimized to significantly reduce procedure duration and improve hepatocyte yield and viability.
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Affiliation(s)
- Meital Charni-Natan
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, POB 12, Rehovot 7610001, Israel
| | - Ido Goldstein
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, POB 12, Rehovot 7610001, Israel
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25
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Oral iron supplementation in iron-deficient women: How much and how often? Mol Aspects Med 2020; 75:100865. [PMID: 32650997 DOI: 10.1016/j.mam.2020.100865] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 05/15/2020] [Accepted: 05/22/2020] [Indexed: 11/23/2022]
Abstract
Iron deficiency and iron deficiency anemia (IDA) are major public health problems worldwide, especially in young women. Oral iron supplementation can be an effective strategy to treat and prevent IDA, but guidelines vary. Some experts recommend doses of 150-200 mg elemental iron per day, with the dose split through the day. However, recent studies suggest this may not be an optimal regimen. The fraction of iron absorbed from high doses of oral iron is low, and unabsorbed iron can cause gut irritation, inflammation and dysbiosis, and these reduce compliance. In recent studies using serum hepcidin profiles and stable iron isotopes to quantify iron absorption in young women, we have shown that: (a) oral iron doses ≥60 mg in iron-deficient women, and doses ≥100 mg in women with IDA, stimulate an acute increase in hepcidin that persists 24 h after the dose, but subsides by 48 h; (b) therefore, to maximize fractional iron absorption, oral doses ≥60 mg should be given on alternate days; (c) the circadian increase in plasma hepcidin is augmented by a morning iron dose; therefore, iron doses should not be given in the afternoon or evening after a morning dose. If rate of Hb response is important, a pooled analysis of our data done for this review indicates that total iron absorption is also higher if twice the target daily iron dose is given on alternate days. In summary, these studies suggest changing from daily to alternate-day schedules and from divided to morning single doses increases iron absorption and may reduce side effects. Thus, providing morning doses of 60-120 mg iron as a ferrous salt given with ascorbic acid on alternate days may be an optimal oral dosing regimen for women with iron-deficiency and mild IDA.
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26
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Hepcidin Peptide Inhibitor as Cardioprotection by Targeting Oxidative Stress and Inflammation in Type 1 Diabetic. Int J Pept Res Ther 2020. [DOI: 10.1007/s10989-019-09912-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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27
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Abstract
BACKGROUND Disorders of serum iron balance are frequently observed in chronic hepatitis C (CHC) patients. Iron overload as well as iron deficiency anemia are common clinical findings in these patients. Variceal bleeding is also a common complication. To date, no study has discussed the influence of esophageal bleeding on iron status in anemic CHC bleeders. OBJECTIVE Was to study reticulocyte hemoglobin content (CHr) and serum hepcidin levels in anemic CHC and to evaluate the influence of variceal bleeding on patients' iron status. METHODS Serum hepcidin levels and CHr were assessed in 65 early phase CHC patients (20 nonanemic, 23 anemic nonbleeders, and 22 anemic bleeders), and 20 healthy controls; and were compared with the conventional indices of iron deficiency including mean corpuscular volume, mean corpuscular hemoglobin, red cell distribution width, serum iron, total iron binding capacity, transferrin saturation and ferritin. RESULTS Hepcidin levels were comparable in patients groups, but were significantly lower in patients than in controls (P = 0.01). Child-Pugh class B patients showed significantly lower hepcidin levels than class A patients. CHr levels were comparable in all groups as well as all iron deficiency indices. Patients with ferritin values or less 100 ng/ml and CHr or less 29 pg/cell or Tfsat or less 16% are more likely to have iron deficiency [odds ratio (OR = 3.93, 95% confidence interval (CI) = 2.54-6.08; OR = 10.50, 95% CI = 1.94-56.55, respectively). CONCLUSION Esophageal bleeding has an almost no influence on iron status in CHC patients. Serum hepcidin content is influenced by CHC disease rather than by anemia associated with or without esophageal bleeding and it could be used as a marker of early hepatic insufficiency. Assessing CHr content could add a potential utility in the detection of iron deficiency in CHC patients.
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28
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Parrow NL, Li Y, Feola M, Guerra A, Casu C, Prasad P, Mammen L, Ali F, Vaicikauskas E, Rivella S, Ginzburg YZ, Fleming RE. Lobe specificity of iron binding to transferrin modulates murine erythropoiesis and iron homeostasis. Blood 2019; 134:1373-1384. [PMID: 31434707 PMCID: PMC6839954 DOI: 10.1182/blood.2018893099] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 08/12/2019] [Indexed: 12/13/2022] Open
Abstract
Transferrin, the major plasma iron-binding molecule, interacts with cell-surface receptors to deliver iron, modulates hepcidin expression, and regulates erythropoiesis. Transferrin binds and releases iron via either or both of 2 homologous lobes (N and C). To test the hypothesis that the specificity of iron occupancy in the N vs C lobe influences transferrin function, we generated mice with mutations to abrogate iron binding in either lobe (TfN-bl or TfC-bl). Mice homozygous for either mutation had hepatocellular iron loading and decreased liver hepcidin expression (relative to iron concentration), although to different magnitudes. Both mouse models demonstrated some aspects of iron-restricted erythropoiesis, including increased zinc protoporphyrin levels, decreased hemoglobin levels, and microcytosis. Moreover, the TfN-bl/N-bl mice demonstrated the anticipated effect of iron restriction on red cell production (ie, no increase in red blood cell [RBC] count despite elevated erythropoietin levels), along with a poor response to exogenous erythropoietin. In contrast, the TfC-bl/C-bl mice had elevated RBC counts and an exaggerated response to exogenous erythropoietin sufficient to ameliorate the anemia. Observations in heterozygous mice further support a role for relative N vs C lobe iron occupancy in transferrin-mediated regulation of iron homeostasis and erythropoiesis.
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Affiliation(s)
- Nermi L Parrow
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO
| | - Yihang Li
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO
| | - Maria Feola
- Division of Hematology-Oncology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Amaliris Guerra
- Division of Hematology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA; and
| | - Carla Casu
- Division of Hematology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA; and
| | - Princy Prasad
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO
| | - Luke Mammen
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO
| | - Faris Ali
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO
| | - Edvinas Vaicikauskas
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO
| | - Stefano Rivella
- Division of Hematology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA; and
| | - Yelena Z Ginzburg
- Division of Hematology-Oncology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Robert E Fleming
- Department of Pediatrics, Saint Louis University School of Medicine, St. Louis, MO
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO
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29
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Sukhbaatar N, Weichhart T. Iron Regulation: Macrophages in Control. Pharmaceuticals (Basel) 2018; 11:ph11040137. [PMID: 30558109 PMCID: PMC6316009 DOI: 10.3390/ph11040137] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 12/10/2018] [Accepted: 12/12/2018] [Indexed: 12/21/2022] Open
Abstract
Macrophages are sentinel cells of the innate immune system and have important functions in development, tissue homeostasis, and immunity. These phylogenetically ancient cells also developed a variety of mechanisms to control erythropoiesis and the handling of iron. Red pulp macrophages in the spleen, Kupffer cells in the liver, and central nurse macrophages in the bone marrow ensure a coordinated metabolism of iron to support erythropoiesis. Phagocytosis of senescent red blood cells by macrophages in the spleen and the liver provide a continuous delivery of recycled iron under steady-state conditions and during anemic stress. Central nurse macrophages in the bone marrow utilize this iron and provide a cellular scaffold and niche to promote differentiation of erythroblasts. This review focuses on the role of the distinct macrophage populations that contribute to efficient iron metabolism and highlight important cellular and systemic mechanisms involved in iron-regulating processes.
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Affiliation(s)
- Nyamdelger Sukhbaatar
- Medical University of Vienna, Center for Pathobiochemistry and Genetics, Vienna 1090, Austria.
| | - Thomas Weichhart
- Medical University of Vienna, Center for Pathobiochemistry and Genetics, Vienna 1090, Austria.
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30
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Transferrin receptor 1 controls systemic iron homeostasis by fine-tuning hepcidin expression to hepatocellular iron load. Blood 2018; 133:344-355. [PMID: 30538134 DOI: 10.1182/blood-2018-05-850404] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 12/04/2018] [Indexed: 02/06/2023] Open
Abstract
Transferrin receptor 1 (Tfr1) mediates uptake of circulating transferrin-bound iron to developing erythroid cells and other cell types. Its critical physiological function is highlighted by the embryonic lethal phenotype of Tfr1-knockout (Tfrc-/-) mice and the pathologies of several tissue-specific knockouts. We generated TfrcAlb-Cre mice bearing hepatocyte-specific ablation of Tfr1 to explore implications in hepatocellular and systemic iron homeostasis. TfrcAlb-Cre mice are viable and do not display any apparent liver pathology. Nevertheless, their liver iron content (LIC) is lower compared with that of control Tfrcfl/fl littermates as a result of the reduced capacity of Tfr1-deficient hepatocytes to internalize iron from transferrin. Even though liver Hamp messenger RNA (mRNA) and serum hepcidin levels do not differ between TfrcAlb-Cre and Tfrcfl/fl mice, Hamp/LIC and hepcidin/LIC ratios are significantly higher in the former. Importantly, this is accompanied by modest hypoferremia and microcytosis, and it predisposes TfrcAlb-Cre mice to iron-deficiency anemia. TfrcAlb-Cre mice appropriately regulate Hamp expression following dietary iron manipulations or holo-transferrin injection. Holo-transferrin also triggers proper induction of Hamp mRNA, ferritin, and Tfr2 in primary TfrcAlb-Cre hepatocytes. We further show that these cells can acquire 59Fe from 59Fe-transferrin, presumably via Tfr2. We conclude that Tfr1 is redundant for basal hepatocellular iron supply but essential for fine-tuning hepcidin responses according to the iron load of hepatocytes. Our data are consistent with an inhibitory function of Tfr1 on iron signaling to hepcidin via its interaction with Hfe. Moreover, they highlight hepatocellular Tfr1 as a link between cellular and systemic iron-regulatory pathways.
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31
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Masajtis-Zagajewska A, Nowicki M. Effect of atorvastatin on iron metabolism regulation in patients with chronic kidney disease - a randomized double blind crossover study. Ren Fail 2018; 40:700-709. [PMID: 30741616 PMCID: PMC6319462 DOI: 10.1080/0886022x.2018.1535983] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 08/09/2018] [Accepted: 10/02/2018] [Indexed: 12/16/2022] Open
Abstract
INTRODUCTION To determine the effect of 6-month administration of atorvastatin on hepcidin and hemojuvelin levels, inflammatory parameters and iron metabolism in patients with chronic kidney disease (CKD) stages 3 and 4. METHODS Thirty six statin- and erythropoiesis-stimulating agent-naive patients with CKD stages 3 and 4 and LDL cholesterol ≥100 mg/dl received atorvastatin or placebo for two 6-month periods in a double blind, randomized crossover study. Hepcidin, hemojuvelin, hsCRP, IL-6, hemoglobin, red blood cell distribution width, iron, total iron binding capacity (TIBC), and unsaturated iron binding capacity (UIBC) were measured before and after each treatment period. RESULTS Hepcidin decreased (from 102 [307] to 63 [170] pg/ml (p > .001)) in the course of statin therapy but remained unchanged after placebo administration (173 [256] to 153 [204] pg/ml, respectively). Hemojuvelin did not change after either part of the study. Both IL-6 and hsCRP decreased following statin therapy (from 8.7 [12.0] to 8.1 [13.9] pg/ml; p = .04 and from 4.7 [4.0] to 4.0 [3.6] mg/l; p = .4, respectively), but did not change after placebo administration. Blood hemoglobin increased slightly but significantly after 6-month statin therapy (from 11.6 ± 1.6 to 11.9 ± 1.5 g/dl, p = .002), and was unchanged after placebo treatment. TIBC and UIBC increased significantly after 6-month statin therapy, and serum iron also tended to increase. The change of eGFR during the study did not differ between the two treatment periods. CONCLUSIONS Statin may have a small but potentially beneficial effect on serum hepcidin, which may lead to improvement of anemia control in CKD patients.
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Affiliation(s)
- Anna Masajtis-Zagajewska
- Department of Nephrology, Hypertension and Kidney Transplantation, Medical University of Lodz, University Hospital and Teaching Center, Lodz, Poland
| | - Michal Nowicki
- Department of Nephrology, Hypertension and Kidney Transplantation, Medical University of Lodz, University Hospital and Teaching Center, Lodz, Poland
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32
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Hepcidin-mediated hypoferremic response to acute inflammation requires a threshold of Bmp6/Hjv/Smad signaling. Blood 2018; 132:1829-1841. [PMID: 30213871 DOI: 10.1182/blood-2018-03-841197] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 09/11/2018] [Indexed: 01/01/2023] Open
Abstract
Systemic iron balance is controlled by hepcidin, a liver hormone that limits iron efflux to the bloodstream by promoting degradation of the iron exporter ferroportin in target cells. Iron-dependent hepcidin induction requires hemojuvelin (HJV), a bone morphogenetic protein (BMP) coreceptor that is disrupted in juvenile hemochromatosis, causing dramatic hepcidin deficiency and tissue iron overload. Hjv-/- mice recapitulate phenotypic hallmarks of hemochromatosis but exhibit blunted hepcidin induction following lipopolysaccharide (LPS) administration. We show that Hjv-/- mice fail to mount an appropriate hypoferremic response to acute inflammation caused by LPS, the lipopeptide FSL1, or Escherichia coli infection because residual hepcidin does not suffice to drastically decrease macrophage ferroportin levels. Hfe-/- mice, a model of milder hemochromatosis, exhibit almost wild-type inflammatory hepcidin expression and associated effects, whereas double Hjv-/-Hfe-/- mice phenocopy single Hjv-/- counterparts. In primary murine hepatocytes, Hjv deficiency does not affect interleukin-6 (IL-6)/Stat, and only slightly inhibits BMP2/Smad signaling to hepcidin; however, it severely impairs BMP6/Smad signaling and thereby abolishes synergism with the IL-6/Stat pathway. Inflammatory induction of hepcidin is suppressed in iron-deficient wild-type mice and recovers after the animals are provided overnight access to an iron-rich diet. We conclude that Hjv is required for inflammatory induction of hepcidin and controls the acute hypoferremic response by maintaining a threshold of Bmp6/Smad signaling. Our data highlight Hjv as a potential pharmacological target against anemia of inflammation.
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33
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Oxidative stress and neurodegeneration: the involvement of iron. Biometals 2018; 31:715-735. [PMID: 30014355 DOI: 10.1007/s10534-018-0126-2] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 07/04/2018] [Indexed: 12/14/2022]
Abstract
Many evidences indicate that oxidative stress plays a significant role in a variety of human disease states, including neurodegenerative diseases. Iron is an essential metal for almost all living organisms due to its involvement in a large number of iron-containing proteins and enzymes, though it could be also toxic. Actually, free iron excess generates oxidative stress, particularly in brain, where anti-oxidative defences are relatively low. Its accumulation in specific regions is associated with pathogenesis in a variety of neurodegenerative diseases (i.e., Parkinson's disease, Alzheimer's disease, Huntington's chorea, Amyotrophic Lateral Sclerosis and Neurodegeneration with Brain Iron Accumulation). Anyway, the extent of toxicity is dictated, in part, by the localization of the iron complex within the cell (cytosolic, lysosomal and mitochondrial), its biochemical form, i.e., ferritin or hemosiderin, as well as the ability of the cell to prevent the generation and propagation of free radical by the wide range of antioxidants and cytoprotective enzymes in the cell. Particularly, ferrous iron can act as a catalyst in the Fenton reaction that potentiates oxygen toxicity by generating a wide range of free radical species, including hydroxyl radicals (·OH). The observation that patients with neurodegenerative diseases show a dramatic increase in their brain iron content, correlated with the production of reactive oxigen species in these areas of the brain, conceivably suggests that disturbances in brain iron homeostasis may contribute to the pathogenesis of these disorders. The aim of this review is to describe the chemical features of iron in human beings and iron induced toxicity in neurodegenerative diseases. Furthermore, the attention is focused on metal chelating drugs therapeutic strategies.
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34
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Mirciov CSG, Wilkins SJ, Hung GCC, Helman SL, Anderson GJ, Frazer DM. Circulating iron levels influence the regulation of hepcidin following stimulated erythropoiesis. Haematologica 2018; 103:1616-1626. [PMID: 29903760 PMCID: PMC6165793 DOI: 10.3324/haematol.2017.187245] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 06/11/2018] [Indexed: 01/01/2023] Open
Abstract
The stimulation of erythrocyte formation increases the demand for iron by the bone marrow and this in turn may affect the levels of circulating diferric transferrin. As this molecule influences the production of the iron regulatory hormone hepcidin, we hypothesized that erythropoiesis-driven changes in diferric transferrin levels could contribute to the decrease in hepcidin observed following the administration of erythropoietin. To examine this, we treated mice with erythropoietin and examined diferric transferrin at various time points up to 18 hours. We also investigated the effect of altering diferric transferrin levels on erythropoietin-induced inhibition of Hamp1, the gene encoding hepcidin. We detected a decrease in diferric transferrin levels 5 hours after erythropoietin injection and prior to any inhibition of the hepatic Hamp1 message. Diferric transferrin returned to control levels 12 hours after erythropoietin injection and had increased beyond control levels by 18 hours. Increasing diferric transferrin levels via intravenous iron injection prevented the inhibition of Hamp1 expression by erythropoietin without altering hepatic iron concentration or the expression of Erfe, the gene encoding erythroferrone. These results suggest that diferric transferrin likely contributes to the inhibition of hepcidin production in the period shortly after injection of erythropoietin and that, under the conditions examined, increasing diferric transferrin levels can overcome the inhibitory effect of erythroferrone on hepcidin production. They also imply that the decrease in Hamp1 expression in response to an erythropoietic stimulus is likely to be mediated by multiple signals.
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Affiliation(s)
- Cornel S G Mirciov
- Iron Metabolism Laboratory, QIMR Berghofer Medical Research Institute, Herston, Australia.,School of Medicine, The University of Queensland, St Lucia, Australia
| | - Sarah J Wilkins
- Iron Metabolism Laboratory, QIMR Berghofer Medical Research Institute, Herston, Australia
| | - Grace C C Hung
- Iron Metabolism Laboratory, QIMR Berghofer Medical Research Institute, Herston, Australia
| | - Sheridan L Helman
- Iron Metabolism Laboratory, QIMR Berghofer Medical Research Institute, Herston, Australia.,School of Biomedical Sciences, Queensland University of Technology, Gardens Point, Australia
| | - Gregory J Anderson
- Iron Metabolism Laboratory, QIMR Berghofer Medical Research Institute, Herston, Australia.,School of Medicine, The University of Queensland, St Lucia, Australia.,School of Chemistry and Molecular Bioscience, The University of Queensland, St Lucia, Australia
| | - David M Frazer
- Iron Metabolism Laboratory, QIMR Berghofer Medical Research Institute, Herston, Australia .,School of Medicine, The University of Queensland, St Lucia, Australia
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35
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Pu Y, Li S, Xiong H, Zhang X, Wang Y, Du H. Iron Promotes Intestinal Development in Neonatal Piglets. Nutrients 2018; 10:nu10060726. [PMID: 29874829 PMCID: PMC6024698 DOI: 10.3390/nu10060726] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 06/02/2018] [Accepted: 06/04/2018] [Indexed: 01/15/2023] Open
Abstract
Early nutrition is key to promoting gut growth and education of the immune system. Although iron deficiency anemia has long been recognized as a serious iron disorder, the effects of iron supplementation on gut development are less clear. Therefore, using suckling piglets as the model for iron deficiency, we assessed the impacts of iron supplementation on hematological status, gut development, and immunity improvement. Piglets were parenterally supplied with iron dextran (FeDex, 60 mg Fe/kg) by intramuscular administration on the third day after birth and slaughtered at the age of two days, five days, 10 days, and 20 days. It was expected that iron supplementation with FeDex improved the iron status with higher levels of serum iron, ferritin, transferrin, and iron loading in the liver by regulating the interaction of hepcidin and ferroportin (FPN). FeDex supplementation increased villus length and crypt depth, attenuated the pathological status of the duodenum, and was beneficial to intestinal mucosa. FeDex also influenced the intestinal immune development by stimulating the cytokines’ production of the intestine and enhancing the phagocytotic capacity of monocytes. Overall, the present study suggested that iron supplementation helped promote the development of the intestine by improving its morphology, which maintains its mucosal integrity and enhances the expression of immuno-associated factors.
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Affiliation(s)
- Yutian Pu
- Key Laboratory of Animal Nutrition and Feed Science (Eastern of China), Ministry of Agriculture, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, College of Animal Science, Zhejiang University, Hangzhou 310058, China.
| | - Shuhui Li
- Key Laboratory of Animal Nutrition and Feed Science (Eastern of China), Ministry of Agriculture, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, College of Animal Science, Zhejiang University, Hangzhou 310058, China.
| | - Haitao Xiong
- Key Laboratory of Animal Nutrition and Feed Science (Eastern of China), Ministry of Agriculture, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, College of Animal Science, Zhejiang University, Hangzhou 310058, China.
- College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
| | - Xiaofeng Zhang
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
| | - Yizhen Wang
- Key Laboratory of Animal Nutrition and Feed Science (Eastern of China), Ministry of Agriculture, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, College of Animal Science, Zhejiang University, Hangzhou 310058, China.
| | - Huahua Du
- Key Laboratory of Animal Nutrition and Feed Science (Eastern of China), Ministry of Agriculture, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, College of Animal Science, Zhejiang University, Hangzhou 310058, China.
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36
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Iron storage disease (hemochromatosis) and hepcidin response to iron load in two species of pteropodid fruit bats relative to the common vampire bat. J Comp Physiol B 2018; 188:683-694. [DOI: 10.1007/s00360-018-1155-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 03/14/2018] [Accepted: 03/14/2018] [Indexed: 01/26/2023]
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37
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Erythroferrone: An Erythroid Regulator of Hepcidin and Iron Metabolism. Hemasphere 2018; 2:e35. [PMID: 31723763 PMCID: PMC6745900 DOI: 10.1097/hs9.0000000000000035] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 02/04/2018] [Accepted: 02/23/2018] [Indexed: 12/21/2022] Open
Abstract
Iron homeostasis ensures adequate iron for biological processes while preventing excessive iron accumulation, which can lead to tissue injury. In mammalian systems, iron availability is controlled by the interaction of the iron-regulatory hormone hepcidin with ferroportin, a molecule that functions both as the hepcidin receptor as well as the sole known cellular exporter of iron. By reducing iron export through ferroportin to blood plasma, hepcidin inhibits the mobilization of iron from stores and the absorption of dietary iron. Among the many processes requiring iron, erythropoiesis is the most iron-intensive, consuming most iron circulating in blood plasma. Under conditions of enhanced erythropoiesis, more iron is required to provide developing erythroblasts with adequate iron for heme and hemoglobin synthesis. Here the hormone erythroferrone, produced by erythroblasts, acts on hepatocytes to suppress hepcidin production, and thereby increase dietary iron absorption and mobilization from stores. This review focuses on the discovery of erythroferrone and recent advances in understanding the role of this hormone in the regulation of iron homeostasis during states of increased erythropoietic demand. Gaps in our understanding of the role of erythroferrone are highlighted for future study.
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Rosati A, Ravaglia F, Panichi V. Improving Erythropoiesis Stimulating Agent Hyporesponsiveness in Hemodialysis Patients: The Role of Hepcidin and Hemodiafiltration Online. Blood Purif 2018; 45:139-146. [PMID: 30959500 DOI: 10.1159/000485314] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 11/14/2017] [Indexed: 12/23/2022]
Abstract
Hyporesponsiveness to erythropoietin stimulating agents (ESAs) is a condition associated with increased mortality. Even after identifying the condition, the causes are difficult to treat and only partially reversible in end-stage renal disease patients. Thus, the role of more recent hemodialysis (HD) techniques in improving such conditions is an emerging issue. However, major randomized clinical trials have not confirmed the results of smaller observational studies in which online hemodiafiltration has shown some efficacy in improving patients' response to ESAs. In our interpretation, these findings are not in contrast, but they can be explained by a better understanding of the interactions between HD and ESAs on iron mobilization, first of all through the role of hepcidin. The kinetics of hepcidin removal through HD combined with the action of selected ESAs may help the clinician in prescribing the best association between HD treatment and ESAs to overcome hyporesponsiveness.
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Affiliation(s)
- Alberto Rosati
- Nephrology Unit, Nuovo San Giovanni di Dio Hospital, Florence, Italy,
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Chow JK, Ganz T, Ruthazer R, Simpson MA, Pomfret EA, Gordon FD, Westerman ME, Snydman DR. Iron-related markers are associated with infection after liver transplantation. Liver Transpl 2017; 23:1541-1552. [PMID: 28703464 PMCID: PMC5696081 DOI: 10.1002/lt.24817] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 06/07/2017] [Accepted: 06/26/2017] [Indexed: 12/21/2022]
Abstract
Though serum iron has been known to be associated with an increased risk of infection, hepcidin, the major regulator of iron metabolism, has never been systematically explored in this setting. Finding early biomarkers of infection, such as hepcidin, could help identify patients in whom early empiric antimicrobial therapy would be beneficial. We prospectively enrolled consecutive patients (n = 128) undergoing first-time, single-organ orthotopic liver transplantation (OLT) without known iron overload disorders at 2 academic hospitals in Boston from August 2009 to November 2012. Cox regression compared the associations between different iron markers and the development of first infection at least 1 week after OLT; 47 (37%) patients developed a primary outcome of infection at least 1 week after OLT and 1 patient died. After adjusting for perioperative bleeding complications, number of hospital days, and hepatic artery thrombosis, changes in iron markers were associated with the development of infection post-OLT including increasing ferritin (hazard ratio [HR], 1.51; 95% confidence interval [CI], 1.12-2.05), rising ferritin slope (HR, 1.10; 95% CI, 1.03-1.17), and increasing hepcidin (HR, 1.43; 95% CI, 1.05-1.93). A decreasing iron (HR, 1.76; 95% CI, 1.20-2.57) and a decreasing iron slope (HR, 4.21; 95% CI, 2.51-7.06) were also associated with subsequent infections. In conclusion, hepcidin and other serum iron markers and their slope patterns or their combination are associated with infection in vulnerable patient populations. Liver Transplantation 23 1541-1552 2017 AASLD.
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Affiliation(s)
- Jennifer K.L Chow
- Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Boston, MA, 02116, USA
| | - Tomas Ganz
- Departments of Medicine and Pathology, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095, USA
| | - Robin Ruthazer
- Tufts Clinical and Translational Science Institute, Tufts Medical Center, Boston, MA, 02116, USA
| | - Mary Ann Simpson
- Department of Transplantation, Lahey Hospital and Medical Center, Burlington, MA, 01805 USA
| | - Elizabeth A. Pomfret
- Department of Transplantation, Lahey Hospital and Medical Center, Burlington, MA, 01805 USA,Division of Transplant Surgery, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Fredric D. Gordon
- Department of Transplantation, Lahey Hospital and Medical Center, Burlington, MA, 01805 USA
| | | | - David R. Snydman
- Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Boston, MA, 02116, USA
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Ambachew S, Biadgo B. Hepcidin in Iron Homeostasis: Diagnostic and Therapeutic Implications in Type 2 Diabetes Mellitus Patients. Acta Haematol 2017; 138:183-193. [PMID: 29136618 DOI: 10.1159/000481391] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 09/08/2017] [Indexed: 12/21/2022]
Abstract
The prevalence of type 2 diabetes is increasing in epidemic proportions worldwide. Evidence suggests body iron overload is frequently linked and observed in patients with type 2 diabetes. Body iron metabolism is based on iron conservation and recycling by which only a part of the daily need is replaced by duodenal absorption. The principal liver-produced peptide called hepcidin plays a fundamental role in iron metabolism. It directly binds to ferroportin, the sole iron exporter, resulting in the internalization and degradation of ferroportin. However, inappropriate production of hepcidin has been shown to play a role in the pathogenesis of type 2 diabetes mellitus and its complications, based on the regulation and expression in iron-abundant cells. Underexpression of hepcidin results in body iron overload, which triggers the production of reactive oxygen species simultaneously thought to play a major role in diabetes pathogenesis mediated both by β-cell failure and insulin resistance. Increased hepcidin expression results in increased intracellular sequestration of iron, and is associated with the complications of type 2 diabetes. Besides, hepcidin concentrations have been linked to inflammatory cytokines, matriptase 2, and chronic hepatitis C infection, which have in turn been reported to be associated with diabetes by several approaches. Either hepcidin-targeted therapy alone or as adjunctive therapy with phlebotomy, iron chelators, or dietary iron restriction may be able to alter iron parameters in diabetic patients. Therefore, measuring hepcidin may improve differential diagnosis and the monitoring of disorders of iron metabolism.
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Affiliation(s)
- Sintayehu Ambachew
- Department of Clinical Chemistry, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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Stoffel NU, Cercamondi CI, Brittenham G, Zeder C, Geurts-Moespot AJ, Swinkels DW, Moretti D, Zimmermann MB. Iron absorption from oral iron supplements given on consecutive versus alternate days and as single morning doses versus twice-daily split dosing in iron-depleted women: two open-label, randomised controlled trials. LANCET HAEMATOLOGY 2017; 4:e524-e533. [PMID: 29032957 DOI: 10.1016/s2352-3026(17)30182-5] [Citation(s) in RCA: 238] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 09/07/2017] [Accepted: 09/08/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND Current guidelines to treat iron deficiency recommend daily provision of ferrous iron divided through the day to increase absorption. However, daily dosing and split dosing might increase serum hepcidin and decrease iron absorption from subsequent doses. Our study aim was to compare iron absorption from oral iron supplements given on consecutive versus alternate days and given as single morning doses versus twice-daily split dosing. METHODS We did two prospective, open-label, randomised controlled trials assessing iron absorption using (54Fe)-labelled, (57Fe)-labelled, or (58Fe)-labelled ferrous sulfate in iron-depleted (serum ferritin ≤25 μg/L) women aged 18-40 years recruited from ETH Zurich and the University of Zurich, Switzerland. In study 1, women were randomly assigned (1:1) to two groups. One group was given 60 mg iron at 0800 h (±1 h) on consecutive days for 14 days, and the other group was given the same doses on alternate days for 28 days. In study 2, women were assigned to two groups, stratified by serum ferritin so that two groups with similar iron statuses could be formed. One group was given 120 mg iron at 0800 h (±1 h) and the other was given the dose split into two divided doses of 60 mg at 0800 h (±1 h) and 1700 h (±1 h) for three consecutive days. 14 days after the final dose, the groups were each crossed over to the other regimen. Within-individual comparisons were done. The co-primary outcomes in both studies were iron bioavailability (total and fractional iron absorption), assessed by measuring the isotopic label abundance in erythrocytes 14 days after administration, and serum hepcidin. Group allocations in both studies were not masked and primary and safety analyses were done on an intention-to-treat basis. The studies were registered at ClinicalTrials.gov, numbers NCT02175888 (study 1) and NCT02177851 (study 2) and are complete. FINDINGS For study 1, 40 women were enrolled on Oct 15-29, 2015. 21 women were assigned to the consecutive-day group and 19 to the alternate-day group. At the end of treatment (14 days for the consecutive-day group and 28 days for the alternate-day group), geometric mean (-SD, +SD) cumulative fractional iron absorptions were 16·3% (9·3, 28·8) in the consecutive-day group versus 21·8% (13·7, 34·6) in the alternate-day group (p=0·0013), and cumulative total iron absorption was 131·0 mg (71·4, 240·5) versus 175·3 mg (110·3, 278·5; p=0·0010). During the first 14 days of supplementation in both groups, serum hepcidin was higher in the consecutive-day group than the alternate-day group (p=0·0031). In study 2, 20 women were enrolled between Aug 13 and 18, 2015. Ten women were assigned to receive once-daily dosing and ten were assigned to receive twice-daily divided dosing. No significant differences were seen in fractional (day 1-3 geometric mean: 11·8% [7·1, 19·4] once daily vs 13·1% [8·2, 20·7] twice daily; p=0·33) or total iron absorption (day 1-3: 44·3 mg [29·4, 66·7] once daily vs 49·4 [35·2, 69·4] twice daily; p=0·33) between the two dosing regimens. Twice-daily divided doses resulted in a higher serum hepcidin concentration than once-daily dosing (p=0·013). No grade 3 or 4 adverse events were reported in either study. INTERPRETATION In iron-depleted women, providing iron supplements daily as divided doses increases serum hepcidin and reduces iron absorption. Providing iron supplements on alternate days and in single doses optimises iron absorption and might be a preferable dosing regimen. These findings should be confirmed in iron-deficient anaemic patients. FUNDING Swiss National Science Foundation, Bern, Switzerland.
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Affiliation(s)
- Nicole U Stoffel
- Department of Health Science and Technology, ETH Zürich, Zürich, Switzerland
| | - Colin I Cercamondi
- Department of Health Science and Technology, ETH Zürich, Zürich, Switzerland
| | - Gary Brittenham
- Department of Pediatrics, Columbia University, College of Physicians and Surgeons, New York, NY, USA
| | - Christophe Zeder
- Department of Health Science and Technology, ETH Zürich, Zürich, Switzerland
| | | | - Dorine W Swinkels
- Department of Laboratory Medicine, Radboud University Medical Centre, Nijmegen, Netherlands
| | - Diego Moretti
- Department of Health Science and Technology, ETH Zürich, Zürich, Switzerland
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Serum Hepcidin as a Diagnostic Marker of Severe Iron Overload in Beta-thalassemia Major. Indian J Pediatr 2017; 84:745-750. [PMID: 28600663 DOI: 10.1007/s12098-017-2375-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 05/08/2017] [Indexed: 01/19/2023]
Abstract
OBJECTIVES To investigate potential usefulness of serum hepcidin in the diagnosis of iron overload in children with β-thalassemia. METHODS A study was conducted on 30 thalassemia major (TM), 30 thalassemia intermedia (TI) and 60 healthy children as controls. Serum hepcidin was measured by Human Hepcidin, ELISA Kit. RESULTS β-thalassemia patients had a higher serum hepcidin compared to the controls (p < 0.001). TM group had higher hepcidin and ferritin compared to the TI group (p = 0.034; < 0.001, respectively). Among controls, hepcidin did not correlate with age (r = 0.225, p = 0.084). Among β-thalassemia patients, it correlated positively with age (r = 0.4; p = 0.001), disease duration (r = 0.5; p < 0.001), transfusion frequency (r = 0.35; p = 0.007), total number of transfusions (r = 0.4; p = 0.003), and ferritin (r = 0.3; p = 0.027). Total hemoglobin and serum ferritin were significantly related to hepcidin, which tended to increase by 0.514 ng/ml with each 1 g/dl rise in hemoglobin (p = 0.023) and by 0.002 ng/ml with each 1 ng/ml rise in serum ferritin (p = 0.002). Iron overload [serum ferritin (SF) ≥ 1500 ng/ml] was independently associated with TM (p = 0.001) and elevated serum hepcidin (p = 0.02). The overall predictability of serum hepcidin in severe iron overload was statistically significant when compared to hepcidin to serum ferritin ratio. CONCLUSIONS Serum hepcidin is elevated in children with β-thalassemia; but this elevation is more evident in TM patients with severe iron overload. Thus, hepcidin can be a potential marker of severe iron overload in patients with TM. Further studies are recommended to compare serum hepcidin and serum ferritin in the prediction of severe iron overload in steady state and during infection or inflammation.
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Bialkowski W, Kiss JE, Wright DJ, Cable R, Birch R, D'Andrea P, Bryant BJ, Spencer BR, Mast AE. Estimates of total body iron indicate 19 mg and 38 mg oral iron are equivalent for the mitigation of iron deficiency in individuals experiencing repeated phlebotomy. Am J Hematol 2017; 92:851-857. [PMID: 28494509 DOI: 10.1002/ajh.24784] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/02/2017] [Accepted: 05/05/2017] [Indexed: 01/08/2023]
Abstract
Iron deficiency anemia is a common clinical condition often treated with tablets containing 65 mg of elemental iron. Such doses can elicit gastrointestinal side effects lowering patient compliance. Oral iron supplements also increase hepcidin production causing decreased fractional absorption of subsequent doses. Frequent blood donors often become iron deficient. Therefore, they were enrolled in a two-year study involving continued blood donations and randomization to receive no pill, placebo, 19, or 38 mg ferrous gluconate for 60 days. Total body iron (TBI) did not change for the subset of donors in the no pill and placebo groups who completed both enrollment and final visits (P = .21 and P = .28, respectively). However, repeated measures regression analysis on the complete dataset estimated a significant decrease in TBI of 52 mg/year for the placebo and no pill groups (P = .001). The effects of 19 and 38 mg iron supplementation on TBI were indistinguishable (P = .54). TBI increased by 229 mg after the initial 60 days of iron supplementation (P < .0001) and was maintained at this higher level with continued iron supplementation following each subsequent donation. The TBI increase was apportioned 51 mg to red cell iron (P < .0001) and 174 mg to storage iron (P < .0001). Changes in storage iron were negatively impacted by 57 mg due to concurrent antacid use (P = .04). These findings in blood donors suggest that much lower doses of iron than are currently used will be effective for clinical treatment of iron deficiency anemia.
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Affiliation(s)
- Walter Bialkowski
- Blood Research and Medical Sciences Institutes, Blood Center of Wisconsin; Milwaukee Wisconsin
| | - Joseph E. Kiss
- The Institute for Transfusion Medicine; Pittsburgh Pennsylvania
| | | | - Ritchard Cable
- New England Region, American Red Cross Blood Services; Dedham Massachusetts
| | | | - Pam D'Andrea
- The Institute for Transfusion Medicine; Pittsburgh Pennsylvania
| | - Barbara J. Bryant
- Department of Pathology; University of Texas Medical Branch; Galveston Texas
| | - Bryan R. Spencer
- New England Region, American Red Cross Blood Services; Dedham Massachusetts
| | - Alan E. Mast
- Blood Research and Medical Sciences Institutes, Blood Center of Wisconsin; Milwaukee Wisconsin
- Department of Cell Biology, Neurobiology and Anatomy; Medical College of Wisconsin; Milwaukee Wisconsin
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Rishi G, Subramaniam VN. The liver in regulation of iron homeostasis. Am J Physiol Gastrointest Liver Physiol 2017; 313:G157-G165. [PMID: 28596277 DOI: 10.1152/ajpgi.00004.2017] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 05/31/2017] [Accepted: 05/31/2017] [Indexed: 01/31/2023]
Abstract
The liver is one of the largest and most functionally diverse organs in the human body. In addition to roles in detoxification of xenobiotics, digestion, synthesis of important plasma proteins, gluconeogenesis, lipid metabolism, and storage, the liver also plays a significant role in iron homeostasis. Apart from being the storage site for excess body iron, it also plays a vital role in regulating the amount of iron released into the blood by enterocytes and macrophages. Since iron is essential for many important physiological and molecular processes, it increases the importance of liver in the proper functioning of the body's metabolism. This hepatic iron-regulatory function can be attributed to the expression of many liver-specific or liver-enriched proteins, all of which play an important role in the regulation of iron homeostasis. This review focuses on these proteins and their known roles in the regulation of body iron metabolism.
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Affiliation(s)
- Gautam Rishi
- Liver Disease and Iron Disorders Research Group, Institute of Health and Biomedical Innovation and School of Biomedical Sciences, Queensland University of Technology, Brisbane, Australia
| | - V Nathan Subramaniam
- Liver Disease and Iron Disorders Research Group, Institute of Health and Biomedical Innovation and School of Biomedical Sciences, Queensland University of Technology, Brisbane, Australia
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Iorember F, Aviles D. Anemia in nephrotic syndrome: approach to evaluation and treatment. Pediatr Nephrol 2017; 32:1323-1330. [PMID: 27999949 DOI: 10.1007/s00467-016-3555-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 11/22/2016] [Accepted: 11/29/2016] [Indexed: 01/01/2023]
Abstract
Nephrotic syndrome is one of the most common glomerular diseases that affect in children. Complications may occur in nephrotic syndrome as a result of the disease itself as well as its treatment. Most of these complications result from excessive urinary protein losses, and control of proteinuria is the most effective treatment strategy. Anemia is one of the many complications seen in patients with persistent nephrotic syndrome and may occur as a result of excessive urinary losses of iron, transferrin, erythropoietin, transcobalamin and/or metals. This leads to a deficiency of substrates necessary for effective erythropoiesis, requiring supplementation in order to correct the anemia. Supplementation of iron and erythropoietin alone often does not lead to correction of the anemia, suggesting other possible mechanisms which need further investigation. A clear understanding of the pathophysiologic mechanisms of anemia in nephrotic syndrome is necessary to guide appropriate therapy, but only limited evidence is currently available on the precise etiologic mechanisms of anemia in nephrotic syndrome. In this review we focus on the current state of knowledge on the pathogenesis of anemia in nephrotic syndrome.
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Affiliation(s)
- Franca Iorember
- Division of Pediatric Nephrology, Department of Pediatrics, Louisiana State University Health Sciences Center, 200 Henry Clay Avenue, Rm 4241, Now Orleans, LA, 70118, USA
| | - Diego Aviles
- Division of Pediatric Nephrology, Department of Pediatrics, Louisiana State University Health Sciences Center, 200 Henry Clay Avenue, Rm 4241, Now Orleans, LA, 70118, USA.
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Wang C, Fang Z, Zhu Z, Liu J, Chen H. Reciprocal regulation between hepcidin and erythropoiesis and its therapeutic application in erythroid disorders. Exp Hematol 2017; 52:24-31. [DOI: 10.1016/j.exphem.2017.05.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 05/03/2017] [Accepted: 05/04/2017] [Indexed: 12/16/2022]
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Knutson MD. Iron transport proteins: Gateways of cellular and systemic iron homeostasis. J Biol Chem 2017; 292:12735-12743. [PMID: 28615441 DOI: 10.1074/jbc.r117.786632] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cellular iron homeostasis is maintained by iron and heme transport proteins that work in concert with ferrireductases, ferroxidases, and chaperones to direct the movement of iron into, within, and out of cells. Systemic iron homeostasis is regulated by the liver-derived peptide hormone, hepcidin. The interface between cellular and systemic iron homeostasis is readily observed in the highly dynamic iron handling of four main cell types: duodenal enterocytes, erythrocyte precursors, macrophages, and hepatocytes. This review provides an overview of how these cell types handle iron, highlighting how iron and heme transporters mediate the exchange and distribution of body iron in health and disease.
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Affiliation(s)
- Mitchell D Knutson
- Food Science and Human Nutrition Department, University of Florida, Gainesville, Florida 32611-03170.
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Ali MK, Kim RY, Karim R, Mayall JR, Martin KL, Shahandeh A, Abbasian F, Starkey MR, Loustaud-Ratti V, Johnstone D, Milward EA, Hansbro PM, Horvat JC. Role of iron in the pathogenesis of respiratory disease. Int J Biochem Cell Biol 2017; 88:181-195. [PMID: 28495571 DOI: 10.1016/j.biocel.2017.05.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 05/01/2017] [Accepted: 05/03/2017] [Indexed: 12/13/2022]
Abstract
Iron is essential for many biological processes, however, too much or too little iron can result in a wide variety of pathological consequences, depending on the organ system, tissue or cell type affected. In order to reduce pathogenesis, iron levels are tightly controlled in throughout the body by regulatory systems that control iron absorption, systemic transport and cellular uptake and storage. Altered iron levels and/or dysregulated homeostasis have been associated with several lung diseases, including chronic obstructive pulmonary disease, lung cancer, cystic fibrosis, idiopathic pulmonary fibrosis and asthma. However, the mechanisms that underpin these associations and whether iron plays a key role in the pathogenesis of lung disease are yet to be fully elucidated. Furthermore, in order to survive and replicate, pathogenic micro-organisms have evolved strategies to source host iron, including freeing iron from cells and proteins that store and transport iron. To counter these microbial strategies, mammals have evolved immune-mediated defence mechanisms that reduce iron availability to pathogens. This interplay between iron, infection and immunity has important ramifications for the pathogenesis and management of human respiratory infections and diseases. An increased understanding of the role that iron plays in the pathogenesis of lung disease and respiratory infections may help inform novel therapeutic strategies. Here we review the clinical and experimental evidence that highlights the potential importance of iron in respiratory diseases and infections.
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Affiliation(s)
- Md Khadem Ali
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Richard Y Kim
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Rafia Karim
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Jemma R Mayall
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Kristy L Martin
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Ali Shahandeh
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Firouz Abbasian
- Global Centre for Environmental Remediation, Faculty of Science, the University of Newcastle, Callaghan, NSW 2308, Australia
| | - Malcolm R Starkey
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | | | - Daniel Johnstone
- Bosch Institute and Discipline of Physiology, The University of Sydney, Sydney NSW 2000, Australia
| | - Elizabeth A Milward
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Philip M Hansbro
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Jay C Horvat
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia.
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Decreasing TfR1 expression reverses anemia and hepcidin suppression in β-thalassemic mice. Blood 2017; 129:1514-1526. [PMID: 28151426 DOI: 10.1182/blood-2016-09-742387] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 01/12/2017] [Indexed: 01/19/2023] Open
Abstract
Iron availability for erythropoiesis and its dysregulation in β-thalassemia are incompletely understood. We previously demonstrated that exogenous apotransferrin leads to more effective erythropoiesis, decreasing erythroferrone (ERFE) and derepressing hepcidin in β-thalassemic mice. Transferrin-bound iron binding to transferrin receptor 1 (TfR1) is essential for cellular iron delivery during erythropoiesis. We hypothesize that apotransferrin's effect is mediated via decreased TfR1 expression and evaluate TfR1 expression in β-thalassemic mice in vivo and in vitro with and without added apotransferrin. Our findings demonstrate that β-thalassemic erythroid precursors overexpress TfR1, an effect that can be reversed by the administration of exogenous apotransferrin. In vitro experiments demonstrate that apotransferrin inhibits TfR1 expression independent of erythropoietin- and iron-related signaling, decreases TfR1 partitioning to reticulocytes during enucleation, and enhances enucleation of defective β-thalassemic erythroid precursors. These findings strongly suggest that overexpressed TfR1 may play a regulatory role contributing to iron overload and anemia in β-thalassemic mice. To evaluate further, we crossed TfR1+/- mice, themselves exhibiting iron-restricted erythropoiesis with increased hepcidin, with β-thalassemic mice. Resultant double-heterozygote mice demonstrate long-term improvement in ineffective erythropoiesis, hepcidin derepression, and increased erythroid enucleation in relation to β-thalassemic mice. Our data demonstrate for the first time that TfR1+/- haploinsufficiency reverses iron overload specifically in β-thalassemic erythroid precursors. Taken together, decreasing TfR1 expression during β-thalassemic erythropoiesis, either directly via induced haploinsufficiency or via exogenous apotransferrin, decreases ineffective erythropoiesis and provides an endogenous mechanism to upregulate hepcidin, leading to sustained iron-restricted erythropoiesis and preventing systemic iron overload in β-thalassemic mice.
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